Reverse Flow Undergravel Filter System? 102 Most Correct Answers

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Keeping the water clean is one of the most important steps in aquarium maintenance. Investing in a quality filter can ensure your water stays fresh and clean without too much effort. In order to choose the best one, it is best to know the different types of filters.

“There are three main types of filtration in any aquarium system. And that’s biological filtration, chemical filtration, and mechanical filtration,” says Nic Tiemens, co-founder of Infinity Aquarium Design. “Biological is the ability to break down harmful organics like ammonia, like nitrate, like nitrite, so you want to make sure you have a filter that has a reputation for breaking down harmful organics.” Mechanical filtration is simply the removal of particles in water. Finally, chemical filtration is the addition of chemical media like carbon or phosphate removers, things that really clean your water so you get clarity and purity.

For crystal clear water, check out the best filtration systems below.

Do you know that if your water is not in the desired PH range according to your fish, it can lead to problems like algae growth, coral growth, damage to the health of your fish, etc.? We highly recommend doing this API water test kit on Amazon.com so you always know the pH level of your aquarium.

Tired of the smaller aquariums and looking to upgrade? Typically, a 55 gallon aquarium is a common choice among novice aquarists. It’s big, but comfortable enough to manage and maintain with ease.

However, the biggest problem with any aquarium, be it 10 gallon or 55 gallon, is filtration. If you don’t integrate the right filter, it can lead to complete chaos. From a lack of water flow rate to improper cleaning, the fish in such tanks die prematurely.

If you have a smaller filter that’s ideal for your current setup, it’s time to upgrade the filter as well. As a rule, there are a few options that need to be considered. There are canister filters, and even the staples hang on back filters. The choice depends on your needs and preferences.

This article will review some of the best filters to invest in for a 55 gallon aquarium.

Here are the best filters for a 55 gallon aquarium – tried and tested

1. MarineLand Magnum Polishing Internal Filter

Starting with an internal filter is always ideal. This will help you control the water flow rate and also control the filtration system. This one from MarieLand is a popular choice among users, especially beginners.

This internal filter is equipped with a high-quality immersion filter. This allows you to make the most of its performance for easier filtration. It takes care of all the filtration needs of the aquarium including mechanical, chemical and biological filtration.

The insides of this filter are integrated with two separate refillable chambers. You can customize the filter media that works best for your tank configuration. It also supports the base carbon filter cartridges to filter out unwanted toxins.

The Micron cartridge in the tank is highly polished with optimal efficiency for best use. The Micron cartridge is included, which is always a plus. Not only will this work for your 55 gallon stacking tank, it will work for up to 100 gallon tanks as well.

The high-performance motor in the tank can seamlessly filter up to 290 gallons of water per hour, which is always a plus. The integrated canister filter in the package also makes the purchase worthwhile. The flow rate of the filter is optimal for different types of fish.

Price: $75.29

Key Specifications:

It comes with a replaceable cartridge

The filter is equipped with a highly polished canister

Supports a flow rate of 290 GPH

It comes with replaceable filter media

advantages

Easy to install and set up

Two-chamber filter media

Self-Priming Features

Easy to clean and maintain

Disadvantages

Makes a whirring sound

2. SeaChem filters for large aquariums

If you are specifically looking for a hanging filter for your 55 gallon aquarium, the SeaChem Large Aquarium Fish Tank Filter is your ideal choice. Besides the reliability of the product, you can also make the most of its features. It supports freshwater, marine and saltwater aquariums.

In addition to brand reliability, the tank is also very energy efficient. You can use it 24/7 and don’t have to worry about it making noise all day long. The filter is also one of the most effective at removing solid waste from the tank.

The self-priming motor remains in the encapsulation. This ensures that you don’t have to spend most of your time fixing the engine. Especially after a power failure, the motor will prime itself and start by itself with external power.

The design of the filter is equipped with a double water inlet with a surface skimmer. This keeps the tank clean and without unnecessary dirt and toxins. Combine that with the adjustable flow rate and a self-cleaning impeller and you don’t have to worry about the features anymore.

The media basket in the filter is customizable. You can fill it with sand and gravel based filters or even charcoal cartridges to keep the chemicals out. The reusable sponge in the packaging is an added bonus, keeping biological waste to a minimum.

The unique and patented flow control valve in this filter is also unique. It allows you to adjust the flow rate and control how much water is filtered. The surface skimmer works, but gets a lot of dirt at times. So if it’s not necessary, you can skip it from the setup.

Price: $49.60

Key Specifications:

It is powered by a 290 GPH internal motor

Supports self-priming functions

Comes with adjustable flow valve control

Designed with a separate heater holder

Customizable filter media basket

advantages

Has ample bio-media capacity

Provides all types of filtration in the tank

Maintains an optimal water flow rate

Backed by a three-year guarantee

Ideal for any aquarium

Disadvantages

The surface skimmer isn’t the best

3. AquaClear Aquarium Filter

AquaClear is a household name when it comes to aquarium filters. This particular model is available in different sizes to suit the size of the aquarium. Besides the unique and stable design, the brand and reliability make it a lucrative choice.

This special aquarium filter is ideal for lazy aquarists. If you’re not looking for a lot of maintenance, this one is the cake. The perfect and adjustable flow capacity of the filter ensures even filtration without clogging.

The filter is integrated with several components including AquaClear foam, activated carbon filter and Bio Max for optimal cleaning. It is a multipurpose filter that also takes care of the solid waste and the biological toxins.

Despite the powerful motor functions, the filter is very energy efficient. That means you won’t have to worry about longer utility bills until the end of the month. The large bio-media capacity allows users to clean the filter every 2-3 weeks.

The main disadvantage of this filter is the external motor. This indicates that it is not a self-priming option. So if the power goes out, you have to start it manually. In the long run, this can put a strain on motor skills.

Besides the main disadvantage, it lives up to its claims. You will witness the optimal biological, mechanical and chemical filtration of the aquarium. The filter volume of this device is 7 times its size, which is pretty good too. Plus, it’s one of the few options backed by a lifetime warranty.

Price: $52.91

Key Specifications:

Made of high quality, BPA-free plastic

Comes with an external motor

Easy installation with maintenance every 2-3 weeks

Ideal for biological, chemical and mechanical filtration

Integrated with customizable filter media room

advantages

Has optimal biomedia capacity

Suitable for any type of fish

Comes with reusable sponge media

Easy to set up and install

Backed by a lifetime guarantee

Disadvantages

Does not have self-priming

4. Penn Plax Cascade 700 external filter

If we had to pick an underrated product, the Penn Plax Cascade 700 Canister Filter ticks the box. Despite the fantastic features and superior design, the aquarium filter doesn’t get that much recognition in the market.

Penn Plax is a leading name in the market for its aquarium products. So when it comes to your external filter, you don’t have to worry. This particular one is versatile and works equally well for freshwater and saltwater tanks.

This particular design is ideal for up to a 65 gallon aquarium capacity. The best selling feature of this filter is the adjustable flow valve. This allows you to regulate the water flow and circulation inside the tank. So if you are worried about the quality, this should meet your needs.

Another advantage is the push button ignition in the filter. In the event of a power failure, you do not have to start the engine from the outside. The machine is sufficiently equipped for this. This is reflected in the durability and longevity of the filter motor.

The canister design contributes to a larger biomedia basket for optimal waste accumulation. You can also adjust the filter media in the machine for optimal cleaning and filtration. The base of the filter features a non-tilting rubber design that keeps it stable in the tank.

With all the good things, however, you have to compromise with the bad. Despite the low engine power of 185 GPH, the energy consumption of this filter is relatively high. This suggests you need to turn it off at intervals to save on utility bills.

Price: $69.95

Key Specifications:

Designed with a 185 GPH powerful motor

Integrated with a simple push button self-primer

Engineered with unique flow valves for adjustable water circulation

Comes with a 360 degree rotatable valve

BPA-free plastic construction with rubber bottom

advantages

silent operation

Easy to set up and install

Ideal for any aquarium setup

Adjustable water flow rate

Slim design

Disadvantages

Not energy efficient

5. SunSun Hw303B 370GPH Pro Canister Filter Kit

It’s always fun to be prepared for the worst. The SunSun Hw303B 370GPH Pro Canister Filter Kit provides you with everything you’re likely to need.

Not only is it versatile, but the product comes with a complete filtration system for future use. This ensures that you have enough filter media and replacement cartridges after a single purchase. So if you’re a beginner with little knowledge, this is a good place to start.

This is one of the best filters for a 55 gallon water capacity. 370 GPH flow rate ensures optimal engine functions with adjustable water flow rates. The canister filter comes with two filter media. They have the basic carbon filter and even the ceramic filter rings for effective cleaning.

In addition to filtering, this is one of the few aquarium filters that supports UV sterilization. This keeps algae and bacterial growth at bay. The reusable filter pads can be washed, so you can reuse them and save a lot of money.

However, the main disadvantage of this filter is the lack of chemical filtration. It only takes care of the biological and mechanical filtration. So if you have high levels of toxins in the aquarium, you will not eliminate them efficiently.

The 370 GPH filter filters 1400 liters of water per hour. So if you are worried about the quality of your aquarium water, you don’t have to worry anymore. Also, because it’s a kit, you get everything that’s in the package, including the filter pads, coarse pads, and media baskets.

Also, the package includes high-quality filter carbon media to remove toxins from the tank. The ceramic rings are also useful to filter the biological waste more easily. Setup is easy too; All you have to do is follow the instructions mentioned on the packaging.

Price: $87.89

Key Specifications:

Comes with all necessary attachments and additional filter cartridges for filtration

Integrated with a powerful 370 GPH engine

Features a canister design

Designed with separate UV sterilization for better usage

Has large media baskets

advantages

Eliminates all germs and bacteria

Reliable and robust design

Features dual and large biomedia capacity

Supports optimal mechanical filtration

Disadvantages

Installation can be a bit confusing for beginners

6. Danner Manufacturing, Inc. Supreme EZ Clean External 55 Gallon Filter

Although not many realize this, external filters are much easier to manage and maintain. They do not need to be cleaned as frequently as the submersible aquarium filters. Among all the options, Danner Manufacturing’s Supreme EZ Clean Filter is a win.

This is a unique patented filter that offers you the convenience of all functions in one device. The dual cartridge system with ample space allows you to fill it with replaceable media for optimal filtration. However, one must pay attention to the flow rate.

The insides of this external filter are integrated with a gravel cleaner. This ensures optimal self-cleaning and prevents the risk of blockages, especially from dirt and other debris.

The water change function warns you when the tank water can no longer be filtered. So you just have to join in and then change the water manually. The only downside is that it cannot remove fine sludge due to the larger pores in the biomedium.

Price: $59.99

Key Specifications:

Comes with a unique patented design

Has an external motor

Integrated with a built in gravel cleaner

Warns when the water needs to be changed

advantages

Versatile and versatile filter

Easy to install

Doesn’t require much maintenance

Filters out biochemical waste and toxins

Ideal for any type of aquarium

Disadvantages

Not ideal for fine silt in the subsoil

7. Penn Plax Cascade Hanging Aquarium Filter

Last but not least on the list is this popular HOB from Penn Plax. This is your ideal option if you want to keep your fish healthy and your aquarium clean. The best selling feature of this filter is the adjustable flow knob.

So if you want to control the flow of water in the tank depending on the residents, you can do it with this filter. Also, the stable and sturdy hanging design of the filter secures and locks to the aquarium for easier placement in the aquarium.

As for the filter’s features, it features a dual-media media cartridge for optimal filtering. The individual choice between the different filter media also allows you to select the most suitable one for your needs. There is activated carbon and polyfiber that work best.

While the former filter is ideal for getting rid of toxins and chemicals, the latter gets rid of the solid waste and associated odor. In addition to the bio media, the filter is also integrated with a sponge filter. This keeps the good bacteria in the tank.

However, there are also some notable downsides to this product. It doesn’t usually come with Bioball filtration. Especially for the price it’s available for, the lack of these features is a bit of a downer.

Price: $53.39

Key Specifications:

Powerful motor supports a flow rate of 300 GPH

Designed with adjustable flow knob for optimal water circulation

Integrated with double-sided media cartridges

Provides multi-layer filtration

advantages

Eliminates mechanical and chemical waste and toxins

Robust and slim design

Extremely reliable branding

Easy to install and operate

Disadvantages

Lack of Bio-Ball filtration

Buying Guide: Things to consider when buying a 50-55 gallon aquarium

If you search online or even check different pet stores, you will be overwhelmed by the number of filtering options. The list is long and plentiful. Therefore, choosing the right product is essential to keep an eye on.

There are a few factors you need to consider and we’ve sorted them out for you:

Start with the type

When it comes to aquarium filters, the types are plentiful. They have the main HOB filters and even external and canister filters. Which one you choose depends on what you are looking for.

If you want to make a long-term investment, external filters are the best choice. However, for a 55 gallon tank, a HOB filter will work just as well. It all depends on your preferences and how things would look in the future.

Check the filter media

In addition to choosing the type of filter, you also need to check the filter media. There is activated carbon, charcoal and some others. The one you choose should be based on the size of the aquarium and the species that live there. If they are smaller, sponge media might be ideal. If they generate a lot of waste, you may need a carbon-based one.

Adjustable flow rate

We cannot stress this enough, but it is very important to pay attention to the water flow rate in the tank. Depending on the species in your tank, you’ll want to mimic the water flow rate they receive in the wild.

A 55 gallon tank should routinely have a minimum flow rate of between 165 and 220 gallons per hour. This is the minimum and should be adjusted according to the needs of your aquarium.

Also, if you have vulnerable fish species like betta that don’t do well in high water flow rates, adjustable flow rate valves come in handy. So always opt for a filter with an adjustable flow rate.

Noise level during operation

With the increasing demands of users, most aquariums are now equipped with whisper-quiet motors. This reduces noise, allowing aquarists to keep the filter on all day.

Otherwise, a poorly designed filter will produce a constant buzzing and humming that’s just irritating. So check out the brands dedicated to developing aquarium filters that produce less noise.

Easy cleaning and maintenance

The last thing anyone wants to do is sit around and consistently clean their aquarium filter. If you are tired of doing the same, we recommend that you choose the product wisely. Most external filters are low-maintenance.

Also, there are some other products that are equipped with a self-cleaning mechanism. Depending on your budget, you can search for one accordingly.

Filter prices

In fact, aquarium filters have different price ranges. Some cost less than $50 and there are some options over $500. It all depends on your own budget. So always prioritize the quality and features of the filter before looking at the price.

frequently asked Questions

How often should I do water changes in my 50-55 gallon aquarium? This is a subjective question. Typically the water changes depending on the type of fish you have. Technically, 2-4 weeks as a standard time period is ideal for water changes. This is the time when the aquarium’s water is cloudy enough to pose a risk of infection. However, if you have a fish or two in a 55 gallon aquarium, you can probably extend the cleaning period to 6 weeks as well.

Conclusion

Purchasing a quality water filter is key to a clean and healthy aquarium. If you have been looking for the best filters for a 55 gallon aquarium, we hope this article will help.

If we had to pick our favorite, we’d recommend checking out the SeaChem Large Aquarium Fish Tank Filter or the MarineLand Magnum Polishing Internal Canister Filter. Both products are unique and probably the best on the market.

If you have any other questions, let us know in the comments. We’re here to help.

Long used in marine aquariums, bottom filters have increased in popularity in freshwater aquariums over the past decade as the importance of the nitrogen cycle has become apparent. These aquarium filters provide an effective means of minimizing levels of ammonia and nitrites in aquarium water and are easy and inexpensive to install. Since they are invisible and do their job without fuss, they can easily be ignored or neglected. Proper setup and maintenance are indeed required for these filters to function effectively over the long term.

Bottom filters work by pulling aquarium water through the layer of gravel at the bottom of the aquarium. In a well-established aquarium, the surface of every particle of this gravel is inhabited by bacteria that metabolize nitrogenous compounds present in the water and convert these compounds toxic to fish into less toxic forms – ammonia to nitrite and then nitrite to nitrate. Nitrate is relatively non-toxic to fish and can be used as a nutrient by aquatic plants or removed from the aquarium by changing the water. Since the gravel grains offer such a large total surface area, a large bacterial population can be supported, ensuring efficient nitrification. Known as the nitrogen cycle, this process is essential to maintaining proper water quality.

The undergravel filter consists of a raised platform on which the gravel is placed and through which the water is drawn. There is a space under the platform into which the water flows after passing the gravel. The filtered water is pumped out of this room and returned to the upper area of ​​the aquarium. Deposits in the aquarium, such as solid fish excrement and uneaten food, are drawn into the gravel by the water flow. Some of this material runs through the entire filter bed and ends up in the space under the filter plate. A small amount of this material is pumped back into the aquarium. However, the water flow under the filter plate is relatively gentle, which is why a significant percentage of this material settles on the aquarium floor. Over time, this material accumulates.

Since the water flowing around this debris is enriched with oxygen, anaerobic decomposition processes are minimized. In fact, there is no evidence that enrichment has any negative impact on water quality. However, if accumulation becomes excessive, it can reduce the water flow rate through the system, thereby reducing the efficiency of the biological filtration process. If the space under the bottom filter plate contains so much material, the only option may be to remove the entire aquarium – in other words, a complete demolition. The plate can then be lifted out of the aquarium and the bottom of the aquarium can be vacuumed clean.

However, it is difficult to determine when, or even if, such an accumulation occurred. If the aquarium does not have a transparent floor that can be seen from below, a visual inspection for deposits is not possible. If it is possible to lower a siphon tube to the bottom of one of the underdrain filter siphon tubes and a significant amount of solids is sucked out, cleaning should be considered. Of course, the extent of debris accumulation remains unknown until the filter panel is lifted out.

All parts of an aquarium accumulate after sufficient time. Even parts that are only exposed to “clean” water, e.g. B. the drain hose of an external filter, develop dirt and slime. Therefore, even with the use of a powerhead to increase the water flow rate under the plate and periodic vacuuming of the gravel – which removes particulates under an undergravel filter – the space under the filter plate is still susceptible to the gradual accumulation of slime, dirt and debris. As mentioned above, this material can reduce the efficiency of the filter by reducing the flow rate of water through the system.

A number of measures can be taken to prevent or prevent such clogging. Increasing the flow of water through the gravel space (e.g. using powerheads instead of air stones) can reduce particle buildup there, but remember that the higher flow rate will also increase the amount of debris sucked through the gravel bed . Regular vacuuming of the space under the filter plate certainly helps. To do this, insert a siphon pipe or the suction hose of a canister or kieselguhr filter into the riser pipe of the underbody filter and suck off the water until no more dirt is visible. However, this technique is not 100 percent effective, and eventually there is a build-up of mucus and other debris that cannot be suctioned out.

The most effective way to prevent debris accumulation in a standard sub-gravel construction is to remove as much debris as possible from the system before it has a chance to work its way through the substrate and into the sub-surface. This can be achieved in two ways. First, an efficient, high-performance filter can remove many solid particles from the water before they can settle on the gravel. Efficient mechanical filtration, in turn, improves the efficiency of the undergravel filter. Secondly, regular vacuuming of the gravel with a suitable suction device will remove significant amounts of debris in the gravel bed and thus allow water to flow freely through the gravel bed. Removing this material from the aquarium, along with the water in which it is suspended, is an excellent way to perform the frequent partial water changes that are an important part of good aquarium maintenance.

Overfeeding the fish can increase the clogging rate of the bottom filter as well as any mechanical filters operated in the aquarium. If the debris sucked out of the gravel contains uneaten food, the fish are overfed. If debris from the fish accumulates so quickly that it requires vacuuming more than once a week or so, the aquarium may be overstocked. In such a case, care must be taken to keep the biological filtration at peak efficiency. Only one-third to one-half of the substrate should be vacuumed at a time, and the area of ​​the gravel bed to be cleaned should be rotated each time. This prevents excessive losses of nitrifying bacteria that can lead to dangerous levels of ammonia or nitrite in the aquarium. Of course, avoiding overstocking is a much preferred method for managing the nitrogen cycle.

A bottom filter operated in countercurrent can also reduce the material problem under the filter plate. With this technique, water that has been mechanically filtered through a canister or other high-efficiency filter is pumped through the siphon tubes into the substrate and then flows through the filter plate and gravel into the aquarium. Very little dirt can collect under the filter plate as only pre-filtered water enters this space and the upward flow direction through the gravel largely prevents dirt from working its way through the gravel bed and under the filter plate. The biological filtration abilities of the bottom filter are retained with this method, although some believe that the backflow inhibits the growth of aquatic plants.

An alternative solution is to perform the biological filtration at a different point in the system that is easily and fully accessible for cleaning. In this setup, the background is completely eliminated. An excellent way to do this is to use an external filter as a biological filter unit. If the filter has sufficient capacity, it can perform both mechanical and biological filtering functions. One or more external line filters can be used for large aquariums.

Canister filters, like undergravel filters, are excellent sites for biological filtration. The water flows relatively slowly through the filter and is in prolonged contact with a large amount of filter material, which serves as a substrate for colonies of nitrifying bacteria. The larger the surface area available for the bacteria, the larger the potential bacterial population. Of course, the longer the water is in contact with the filter media, the greater the potential efficiency of the nitrification process. Thus, a large volume canister filter with a relatively low flow rate provides excellent conditions for the two-stage conversion of ammonia to nitrate. A good rule of thumb for filter flow rates is no more than four or five aquarium volumes per hour.

Perhaps even better than a canister filter in its biological filtration capacity is a trickle or wet/dry filter. In this design, aquarium water is dripped or sprayed over a bed of substrate medium on which the nitrifying bacteria grow. The water is then collected and pumped back into the aquarium. The volume of substrate media is typically equal to or greater than a comparable canister filter and the trickle filter offers the added benefit of highly efficient return water aeration. Water is aerated by contact with air at its surface. As the aquarium water trickles down over the nitrifying substrate, it forms a thin film around the surfaces of the filter media and offers a large surface area to the surrounding air, allowing for rapid and effective gas exchange. Oxygen dissolves from the air into the water, while carbon dioxide escapes in the opposite direction. The aerobic nitrifying bacteria receive the oxygen they need for their activities, and the water returning to the aquarium is saturated with oxygen and has released excess carbon dioxide.

External filters, which typically hang from the back of the aquarium, while capable of offering both mechanical and biological filtration, ultimately outperform mechanical filters over biological filters. Because the gravel bed of a soil filter simply offers a larger surface area for bacteria than the medium of a power filter. For sparsely stocked aquariums, an external mesh filter may be sufficient, but a higher density of biological filtration is often required for aquariums with a higher fish density. For this reason, external mesh filters are often combined with bottom filters. The strength of one complements the weakness of the other for the overall benefit of the fish in an aquarium.

These power filters can pump a lot of water through their media in a short time. The advantage of this: The more often the water flows through the filter in a certain period of time, the better the filter removes suspended matter. After all, this is the basis for effective mechanical filtration. However, the high flow rate means less time for the water to contact the bacterial substrate. Also, the volume of filter material in a typical high-efficiency filter is much less than a canister filter that is likely to be used in aquariums of the same size. In fact, such filters often use cartridge media, which provides only about a half inch of material through which the water will flow. The result is less surface area for bacteria to attach and therefore less potential for ammonia and nitrite oxidation.

Another simple way to provide biological filtration is to use a sponge filter. These use a stream of air to draw water through a porous sponge material, which has the nitrifying bacteria in and on it. Due to the large surface area that the sponge provides, nitrification is very efficient. Water flow through the sponge can be increased by using a powerhead instead of an airlift. Due to the small pore size of sponge filters, they are easily clogged with solid waste material. Luckily, they’re just as easy to clean by taking them out of the tank and popping them in water that’s about the same temperature as the tank. Water that is too hot, too cold, or overly chlorinated should not be used as this will kill the bacteria colonizing the sponge.

Undergravel filters, while not the only method of biological filtration available, retain their popularity because they do a good job, are easy to use, and are relatively inexpensive. Alternative methods such as canister or trickle filters, while equally effective, are far more expensive. Sponge filters are much smaller than most bottom filters and have a lower nitrification capacity. While it is true that biological filtration is essential to the well-being of most aquariums, it is also true that the exact location of such filtration in the system is irrelevant. Regardless of how the required nitrification is carried out, the most important thing is that all the necessary maintenance work is carried out regularly and conscientiously. In this way, the long-term success of the aquarium and the satisfaction of its owner is increased.

Posted by: Chewy Editorial

Featured Image: Via Joel Bez/Flickr

With all the technological advances in the aquarium hobby, I thought it would be nice to take a look at one of the most rudimentary and long-lived devices in the industry – the bottom filter.

Background filters have a pretty bad reputation. They are sometimes considered a relic of aquarium history, but are they still usable? Some hobbyists swear by them and some hobbyists swear by them. How your tank performs with an undergravel filter depends on a few factors – setup and maintenance. Let’s take a look at some of the most common problems related to undergravel filters and explore some solutions.

The problem: They don’t work well enough. Some say bottom filters are inefficient in tanks with a lot of fish.

The solution: Proper setup is very important in filtration. This applies in particular to underground filtration. Using the right size and amount of gravel plays an important role in how well your filter will perform. To ensure maximum efficiency from your filter, you need to make sure you have at least 2 to 3 inches of gravel over the filter plate. The gravel should be of mixed quality, but make sure you don’t have anything so small that can slip under or through the grate. You also want the gravel to be evenly distributed across the soil. Because water flow follows the path of least resistance, an area with less gravel will receive more flow than an area with more gravel. This leads to a less efficient use of the entire filter plate. Another thing to watch out for is using large chunks of stone or wood laid flat on the gravel. These ornaments can restrict the flow across the area.

Another recommendation: Use compressed sand air vents instead of compressed paper air vents. Paper vents clog quickly. You should replace the air vents every month regardless of which ones you use, but the sand air vents work better over longer periods of time.

The problem: They are DIRTY! Many hobbyists have horror stories about the amount of dirt that accumulates under the filters over the years. Another complaint is that they are troublesome to maintain.

The solution: Fish waste and other debris is pulled down through a debris under the filter plate, making it easy to see why someone might think it was dirty. People assume that if you have undergravel filtration you shouldn’t vacuum the gravel because they think that would destroy or suck up the beneficial bacteria. Proper maintenance, however, will ensure that excessive litter and debris does not accumulate under the slab.

To keep your filtration running at peak performance, you should perform weekly water changes. Mentally divide your tank into quarters. Select a quarter of the tank each week and vacuum the gravel in that section. Go about half an inch deep into the gravel with your gravel siphon. This should remove a good amount of the dirt that settles under the filter plate while preventing the bacterial colonies from being completely wiped out. It should also allow the bacteria to recolonize the area before you need to vacuum the next section. If you follow this schedule, your undergravel filter should not accumulate excessive waste or produce nitrates in large quantities.

Simply put, undergravel filters have been around for so long because they work. The low-tech and simple device can be used successfully for years with proper maintenance. Keep your tank well stocked (don’t overload it), don’t overfeed, and keep water changes on schedule. You should have as much success with an undergravel filter as with the more advanced filtration techniques available on the market today. Give an underbody filter a try…with the right setup and maintenance, it can be a dependable and cost-effective tool.

Many Thanks,

craig

View Full Version : Soil filter and sand?

steph0990 Hey I’m a newbie when it comes to tanks

i’m really into “aquascaping” with living plants and such

and I’ve been digging into what sand looks like PLUS I’ve heard it’s better for live plants AND easier to clean up….

BUTTTT I have a UGF and don’t really care about switching filter types

UGF works fine for me

and if it ain’t broke don’t fix it right ?thumbs2:

Ahah my question is since sand is so fine could I use it with my UGF, if so what kind? (Links to products would be great 🙂

Fishguy2727 Well not sure so far. It can take years for tanks to crash, and this is exactly what UGFs are very vulnerable to. A HOB power filter is really a much better option (I recommend AquaClears).

As for sand, I like the Estes sea sand because it is very consistent in size, good size, comes in multiple colors and is cheap. I’ve used it on plants with great results.

steph0990 lol what i meant by fine i meant FINER than gravel

and what do you mean by crash?!

as the water quality go down?

toddnbecka Sand and UGFs are generally not compatible, nor are rooted plants unless potted. I have set up a 75 with gravel substrate with 2 Aquaclear 110’s connected to the UGF slab lift pipes and a couple of other tanks set up for back flow with powerheads pushing water through the slabs and substrate.

I use a small type of gravel instead of sand in my tanks without UGFs. Looks like sand for the most part, but the larger grains are easier to vacuum and keep clean. Check your lfs for different gravel sizes/grades.

A backflow setup with a layer of bulk filter media between the plates and the sand would be your best bet, but I think rooted plants would be a problem as the roots grow into the filter media. Personally, I’m sticking with (live) floating plants like Najas, Hornwort, Amazonian Frogbit and Duckweed.

Mermaid Wannabe They call them undergravel filters because they’re designed for use under gravel. Otherwise they would be called sub-sand filters. Sand would likely accumulate under the plate. Sand and UGFs do not get along.

– Wannabe mermaid

Lady Hobbs And to reiterate what has already been said…….. 🙂

You can’t use sand and UGF and you can’t have UGF with plants. People who use UGF generally use them in rock tanks with reverse pumps to push the dirt up and then other filters to remove what’s being pushed up. They don’t filter well enough when used alone.

Plants also thrive much better in potting soil.

steph0990 thanks guys!!

While I don’t agree that UGF sucks, I’ll get either an Aquaclear 50 OR a Tetras Whisper 70 along with my UGF and probably make a finer gravel.

Thank you for your help 🙂

toddnbecka Take the aquaclear rather than the whisper, you’ll be a lot happier in the long run. Check E-Bay, you can usually find a good deal on a used Aquaclear if you don’t want to spend the money on a new one.

Sandz Good luck Steph, but please remember that you 1) asked for advice and 2) admitted that you are a noob in this area… I strongly encourage you to embrace the idea of ​​using a UGF with plants rethink. They are NOT okay to put together. One way around this is to use slate rock to “pot” your plants in the tank. I have a friend with a 150gal who does this and it works fine.

ILuvMyGoldBarb I wanted to stay out of this one but decided against it as the OP deserves some accurate info.

Firstly yes you can certainly use sand with a UGF (how do you think people filtered early sea tanks?!?)

Second, yes you can have live plants with a UGF.

It all depends on the right setup. Of course you can’t just throw sand on a UGF, you need something to keep the sand from sinking in. A thin layer of gravel and a layer of nylon webbing will solve both of the problems you’re struggling with. You can’t completely cover the bottom of the tank with plants, but you can still keep live plants. You can also not use very fine sand. Something like an Estes Marine Sand would probably work just fine.

Is it the best form of filtration out there? No, but it’s far from outdated, it just requires the right knowledge to set it up.

Fishguy2727 Get an AquaClear.

What size tank is that? Remember that you need a filter that is at least twice the actual tank size.

Although some people use UGF with no problem, it’s much easier for people to just put a HOB there and not have to worry about it. If they neglect it, they can clean the filter and not risk spoiling the whole tank. I personally see no reason to use a UGF when there are so many simpler, more effective and less risky methods.

dbosman The same applies to the fact that plants can live well on UGF plates. Some of the roots will get through and under the slab, but if you don’t rip the plants out regularly, that’s not a problem.

Sucking debris into the gravel is good for a planted tank. It’s packed with nutrients. Most planted aquarium enthusiasts can’t siphon their gravel. Too many healthy plant roots. Malaysian trumpet snails are great for stirring up the substrate. These, too, can get out of control.

What’s bad about UGF filters is a problem that affects too many things. Lack of knowledge and salespeople making up answers when they don’t know what they’re talking about. Most people don’t really pay attention to their tanks. Set it up, top up the water when the filter gets noisy, buy new fish every few months to replace what has died, and complain in a few years when the aquarium crashes. Pointing out that the owner poisoned the tank by never changing the water will only make you unpopular.

Having been involved with aquariums for the most part over the past fifty years, I have had the opportunity to see several technology cycles. I have a 70 gallon tank with UGF panels with performance heads (and performance filters) and light blue epoxy coated gravel. My wife chose the color. None of my planted aquarium buddies like the gravel. The last massive plant removal included a 10 gallon tank full of seaweed, a 10 gallon tank full of various mosses, a 5 gallon bucket full of java fern, and several shoeboxes full of other plants. The money from the sale of the shrimp was paid for a nice batch of crystal red shrimp

There was once an old man in Michigan who raised and raised discus in large tanks with a sandy bottom and lots of pond plants. What he didn’t have were massive daily water changes or filters. People always said it wasn’t possible. He didn’t argue or try to prove anything. He simply bred and sold discus.

One area where UGF panels are making a comeback is in shrimp tanks. A UGF plate with a hob that draws water through the gravel is perfect for preventing shrimp from being sucked into the filter.

Lady Hobbs The big difference here is that this is a newcomer to aquariums and is trying to plant an aquarium for the first time. Very different from being an expert who knows about backup pumps and how to work around the problems of using a UGF. A much easier way is to just remove the UGF and use its sand because we all like moving our plants when we start this hobby.

They probably need to address their problem with additional filtering and plant lighting before doing anything else now. Is there no point in planting a tank without the right lighting?

steph……can you please give me more information, how big is your tank and what kind of lights do you have?

MCHRKiller IMHO the UGF gets a bad rap because people tend to forget it’s a filter and never clean its media…ie the substrate. It’s also very possible to use it with sand, but I would steer clear of fine sand and focus more on a finely crushed silica sand. These somewhat coarser-grained quartz sands can be absorbed very well and do not compact like many fine-grained sands. A roll of polyfiber placed on top of the UGF board before adding the sand would work best to prevent it from falling into the boards.

Would I put heavily rooted plants in the substrate of a UGF? No, the roots would be damaged by properly cleaning the sand, not to mention it would be much more difficult to keep it clean with these heavily rooted plants. These plants also require heavy substrate fertilization which would also be useless in a UGF as the ferments would be sucked away. You can grow plants like ferns, anubias, mosses and floating plants with very good success and keep your heavily rooted plants like swords and crypts in pots for easy care.

Using such a setup isn’t “wrong”, but there are undoubtedly better and definitely easier ways to get your desired setup. Many consider UGFs to be old technology, which they are, but that doesn’t mean they’re useless. It’s more work to keep a UGF working well than it is to keep a stovetop or canister running.

I would use sand:

http://www.substratesource.com/index.php?p=substrate&pn=NM0104

The Scrup FYI polyfilter will be 100% clogged in a year or two, possibly sooner in this application. Mine gets a nice impermeable barrier after about a month in my HOB’s, needs about 2-3 months in the swamp. This depends on the total surface area and flow rate, as well as the biological load.

Lady Hobbs How about a plastic shield….like a window pane?

toddnbecka I have used bulk filter media (blue/white bonded pad) to separate layers of crushed coral and black gravel on UG filter plates in some tanks. There are powerheads with Quickfilter cartridges (also filled with the same filter media or sponges) set up to run the plates in counter-current. Most of the dirt collects in the quick filters or the sponge filters (or canisters on the 55) which are flushed out during partial water changes. The layer of filter media in the 55 has not been moved in years and still shows no significant accumulation of debris. The 29er with the sponge filter has been disassembled and cleaned twice in the past few years, but it wasn’t because the filter media was laden with dirt or impeded the flow of water through the substrate.

MCHRKiller I have been using a UGF as extra filtering on my 100G for well over a year when housing medium sized SA cichlids…it wasn’t really all that dirty as a good gravel vacuum kept it clean. But that’s the whole key to a UGF…keeping the substrate/medium clean over the platters. It’s best to put what is on 2 sheets so you can easily remove half of it while stacking the entire substrate on the other side. That way it wouldn’t be such an ordeal if it had to be changed.

steph0990 aha sorry people haven’t been around to check my thread for a long time.

great ideas for using sand and UGFs..first of all i have a 40cm high tank..i have decided to use an aquaclear 70 as a filter with a sand substrate..it has been running for a few days now..will run it about another eek and 1/2 with no fish (I have extra stability and top fin bacteria supplement)

toddnbecka I use Aquaclear filters on several pools with ‘sand’ substrate and put sponges over the inlets to keep the impellers from being destroyed. Cichlids are particularly bad at picking up and spitting out sand and on more than a few occasions I have found it to have piled up around the bottom of the inlet sponge covers. The replacement penguin powerhead sponges work best IME, they are coarse enough not to clog too quickly.

sskwirl I have no problems in my cichlid tank. 125 gallons, sand, live plants and UGF. Now I have inverted powerheads that create some cool quicksand in some areas from time to time when my cichs come to dig, but they’re easily fixed with a big rock. I’ve been using this system for several years and haven’t had any problems with it or the dreaded tank crash. I do a pretty good job of keeping it clean and I have a canister filter too.

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In the aquarium trade, bottom filters are an odd holdover. Powered by noisy but nearly indestructible air pumps, they were once ubiquitous. Before the market was dominated by small, quiet magnetic drive pumps, there was rarely an aquarium without the well-known plastic risers. The “UGF” are now generally considered obsolete, but they’re cheap and simple enough that they’ll never go away entirely.

Whether bottom filtration still plays a role in aquariums is a question with many answers. In aquaponic systems, however, these ancient reserves offer some surprising benefits.

To be clear, a bottom filter is only useful in an aquaponic system with gravel or other substrate in the bottom of the aquarium. Whether it’s a good idea to leave something on the bottom of the tank is a matter of debate among aquaponic professionals; There are some potential downsides. However, in remodeled aquariums and display systems, looks matter and a bare glass floor just isn’t much to look at. A gravel bed also provides a richer environment for fish and allows for more natural behavior

Not all aquaponic systems use additional filtration. In many cases, media bed attachment provides adequate solids removal. However, additional filters offer real benefits as they help correct any imbalance between production and breakdown of fish waste. The added stability keeps fish and plants healthier. This is especially important in smaller systems where a small change in conditions can have an oversized effect on water chemistry. Aeration in aquariums is also important; In addition to the oxygen requirements of densely stocked fish, waste breakdown can consume or displace oxygen.

So what if there was a solution to all these problems? A mechanical and biological filter media that provides extra filtration where it’s needed most – in the fish tank – and also provides extra aeration? And what if it made your aquarium look beautiful too? If you’ve followed this far, you probably know exactly where this is going because there is such a thing: an undergravel filter.

And that’s not all! The benefits of this ancient technology go even deeper. As? First, consider the way most people start out with aquaponics: small systems, either ready-to-go kits or DIY, with a few aquarium fish and a small media bed. These systems, like almost all media bed hydroponics and aquaponics, are mostly variations on an ebb and flow design. Large ebb and flow systems often have additional circulation or aeration, but small systems may not. This means that the water in the aquarium can remain stagnant most of the time, resulting in a constant, stressful surge in ammonia and dissolved oxygen as it builds up and is then processed during the flood cycle. A few extra filters may not even help with this, as many styles work in-line with the main pump or are diverted from the line and only active when the main water flow is on. An undergravel filter, on the other hand, is exactly where it needs to be. They are also typically air powered, allowing them to run constantly independent of the system pump.

Concerned about solids buildup in your system? Don’t be! Waste solids can clog media beds, coat plant roots, and accumulate into toxic anaerobic sludge if not broken down quickly. Large structures often have entire separate equipment for handling excess solids, including techniques that remove the solids to a separate mineralization tank where they can be agitated and aerated until they break down into a usable, nutrient-rich liquid form. A properly maintained undergravel filter can function much like a small mineralization tank, drawing solids into an open plenum at the bottom of the tank and holding them while they are broken down in the constant gentle flow of water.

Of course, no technology is perfect, even the simple ones. A bottom filter needs to be cleaned from time to time, either by backwashing with a water pump or by “vacuuming” with an aquarium siphon. Stirring the gravel regularly to remove organic debris can help reduce maintenance requirements. Because the risers are a set height, a UGF will not function properly when the water level drops. Therefore, it is important to keep up with refilling. Perhaps the biggest downside is installing one at all; It can be difficult to find UGFs in many sizes these days, meaning you may have to modify or build your own filter unless you are setting up a system based on a standard aquarium size. In any case, it must be installed before adding gravel, or all gravel must be removed. Finally, although they’ve come a long way, the air pumps that power the filter generate strong vibrations and can be noisy.

The undergravel filter is an old, simple technology and in most cases has been replaced by newer devices that are simply more effective. But if you run a small aquaponic system, take a different look! The UGF is cheap, simple, and offers a surprising array of benefits, replacing a number of other more complicated features and devices that a simple system might not really need.

You can clean your aquarium gravel without a vacuum cleaner. Credit: Andrey Nikitin/iStock/GettyImages

Cleaning your aquarium gravel with a vacuum cleaner made specifically for the aquarium is the easiest cleaning method. Aquarium vacuums are designed to quickly and easily remove leftover food and other debris that settles on the bottom of the aquarium. However, an aquarium gravel vacuum is not the only alternative.

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First pull out your fish

Although you do not have to remove your fish from the tank when using an aquarium gravel vacuum, you should remove them if you are cleaning the tank without a siphon. Cleaning your aquarium gravel without a vacuum will stir up silt and debris that can be unhealthy for them.

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Fill a bucket or other clean container with water from your aquarium and carefully transfer the fish to the bucket using a landing net. Make sure the bucket is very clean because, according to the Fish Tank Club, even the tiniest trace of chemical residue can harm fish. A bucket or container dedicated solely for your fish’s use since it’s new is the safest option.

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Remove the gravel

Scoop up a few cups of gravel from the bottom of the tank and set aside without rinsing. This gravel contains beneficial bacteria that help break down ammonia from fish waste into less harmful nitrates. It’s important to keep some gravel uncleaned so these bacteria can easily recolonize after your tank is cleaned.

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Place the remaining gravel in a colander and rinse thoroughly under running water, stirring with a plastic-gloved hand. Make sure the gloves, strainer and any other tools and utensils you use are strictly for use with your fish to ensure no chemical residue is carried over.

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Once the water under the strainer is clear, return the gravel to the tank. Add the cups of dirty gravel you set aside and mix thoroughly with the clean gravel. According to Fish Tank Master, this method is most effective when algae are growing in your substrate.

Try an alternative method

Caring Pets suggests a second method of cleaning aquarium gravel without a filter that doesn’t require removing the gravel at all. This method is ideal if you have live plants as removing them from the tank can damage the roots and ultimately kill the plants.

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First, remove your fish from the tank along with any decorations. Keep your live plants rooted in the gravel and, if necessary, push the plant and surrounding gravel to one side of the aquarium.

Stir up the gravel with your hand and work around the live plants. Mix the gravel thoroughly to keep debris trapped between the stones floating in the water. Next, submerge 1/3 to 1/2 of the muddy water from the tank. The remaining water contains the healthy bacteria needed to replenish your aquarium.

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Say hello to your little friends

Algae eaters and snails can also help clean your gravel. The best varieties for cleaning your aquarium gravel are those that like to dig under the substrate.

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Malaysian trumpet snails are detrivores — meaning they devour both plant matter and protein they find in the gravel. These hard-working snails won’t gobble your plants, however, and will actually help them by aerating the roots, according to Nualgia Aquarium.

Most other algae-eating creatures don’t dig per se. And not all will eat plant matter, algae, and leftover fish food. You also need to consider if your chosen algae eaters will be attacked by larger aquarium mates. Cherry Shrimp, for example, are good at scavenging all types of detritus, but larger tankmates will hunt and eat them.

Siamese algae eaters are another smart addition. Not only do they eat all kinds of algae, they also help fight flatworms and gorge on pretty much any type of waste.

Matt Clarke answers some of the most frequently asked questions about background filtration.

How do soil filters work?

A sub-gravel filter is a slatted grid that forms an intermediate floor that allows a layer of gravel to be suspended over a space filled with water. One or more vertical tubes called airlifts (or elevators) are attached to the slab through which water is drawn using a powerhead or an airstone (powered by an air pump).

The suction created draws water and solid waste into the gravel, providing a source of oxygen-rich water for beneficial nitrifying bacteria to remove the resulting pollutants from the water. This means that the filter works both mechanically, by trapping debris, and biologically, by acting as a colonization site for the bacteria that break down the fish’s waste.

Are you good?

Under gravel tends to be more labor intensive to maintain than internal filters and can cause problems in planted aquariums.

However, they are cheap to buy and run, and have a much larger surface area than most internal power filters. This means that they are theoretically able to endure a greater load of pollution once the bacteria have settled in the filter. If not cared for properly, they can cause a number of problems.

How much gravel should I put on it? And what kind should I use?

Research suggests that the minimum depth should be 76mm/3in and the optimum gravel size should be between 2mm and 5mm. If the gravel size is too small, or if you add sand, it will fall down and clog the slots and restrict water flow through the filter bed. As a general rule of thumb, allow about 10 lb of gravel per square foot, or about 45 kg per square meter.

What flow rate do I need?

A flow rate of 60 gph/272 lph per square foot is best when the filter is at the optimal depth of 76 mm/3 inches. The flow rate should be higher when the bed is deeper.

Undergravel doesn’t need cleaning – right?

Undergravel filters need to be cleaned to function properly. If the sucked dirt is not removed, it will eventually slow the flow of water through the bed. This reduces the amount of oxygen getting to the beneficial bacteria, leading to poor performance and degrading water quality. When the bed becomes clogged, toxic chemicals like hydrogen sulfide can build up. Nitrate (and phosphate) levels can also rise to extremely high levels if cleaning is inadequate.

How often should I clean the gravel?

The frequency of gravel cleaning really depends on how dirty it gets and the water quality. Tanks with large messy fish will require more maintenance than those with small numbers of tiny fish. While thorough cleaning is essential, it likely has some impact on performance. According to some research, many of the bacteria present on a sub-gravel filter bed are tied to trapping detritus. A thorough cleaning removes a lot of dirt in one fell swoop and can reduce the bacterial population by 40-66%, reducing nitrification.

Regular cleaning, however, prevents the accumulation of detritus, so the bacteria are more likely to attach themselves to gravel. A quick cleaning every week is believed to have less of an impact than having the dirt build up over a month and then removing it with a gravel cleaner.

My filter seems to be clogged. How can I unclog it?

Too infrequent gravel cleaning can cause the slots under the plate to clog. Insert a siphon tube into the buoyancy and attempt to siphon the water from under the panel. If vacuuming alone doesn’t work, try gently blowing the hose down to loosen any trapped debris, then start vacuuming again.

If that fails, as a last resort you may have to disassemble the tank and scrub the plate with a toothbrush. Make sure you only wash the gravel with water from the tank. Never wash the gravel in tap water or replace it with new ones, otherwise you will lose the beneficial bacteria and the water will become dirty quickly.

Does it come in any size?

Bottom filters are available in a range of standard sizes to fit snugly in the bottoms of most common tanks. If you have a larger tank you can use multiple plates provided you add enough pumps to ensure adequate flow through the filter. Some manufacturers make small panels that can be joined together to make custom filters for large or irregularly sized tanks.

My plants are not growing very well. Is that because of my soil filter?

Unfortunately, few plants grow well in tanks with a bottom filter. This is thought to be because they pull oxygen over the plant’s roots and, like other filters, oxidize nutrients and expel carbon dioxide.

Choose plants that don’t need to be rooted directly into the gravel, like anubias and java fern. Or place specimen plants in clay pots partially filled with laterite, a nutrient-rich clay.

My cichlids expose the filter when spawning. Is this a problem?

When part of the plate is exposed, the water flows through the whole, bypassing much of the filter bed. Underworld (01509 610310) make a special plastic mesh material called a gravel basket that can be cut to size and placed between two layers of gravel. Burrowing cichlids can only properly dig down to the gravel instead of exposing the whole panel, which keeps the filter functional.

This article was first published in the September 2002 issue of Practical Fishkeeping.

View Full Version : Soil filter and sand?

steph0990 Hey I’m a newbie when it comes to tanks

i’m really into “aquascaping” with living plants and such

and I’ve been digging into what sand looks like PLUS I’ve heard it’s better for live plants AND easier to clean up….

BUTTTT I have a UGF and don’t really care about switching filter types

UGF works fine for me

and if it ain’t broke don’t fix it right ?thumbs2:

Ahah my question is since sand is so fine could I use it with my UGF, if so what kind? (Links to products would be great 🙂

Fishguy2727 Well not sure so far. It can take years for tanks to crash, and this is exactly what UGFs are very vulnerable to. A HOB power filter is really a much better option (I recommend AquaClears).

As for sand, I like the Estes sea sand because it is very consistent in size, good size, comes in multiple colors and is cheap. I’ve used it on plants with great results.

steph0990 lol what i meant by fine i meant FINER than gravel

and what do you mean by crash?!

as the water quality go down?

toddnbecka Sand and UGFs are generally not compatible, nor are rooted plants unless potted. I have set up a 75 with gravel substrate with 2 Aquaclear 110’s connected to the UGF slab lift pipes and a couple of other tanks set up for back flow with powerheads pushing water through the slabs and substrate.

I use a small type of gravel instead of sand in my tanks without UGFs. Looks like sand for the most part, but the larger grains are easier to vacuum and keep clean. Check your lfs for different gravel sizes/grades.

A backflow setup with a layer of bulk filter media between the plates and the sand would be your best bet, but I think rooted plants would be a problem as the roots grow into the filter media. Personally, I’m sticking with (live) floating plants like Najas, Hornwort, Amazonian Frogbit and Duckweed.

Mermaid Wannabe They call them undergravel filters because they’re designed for use under gravel. Otherwise they would be called sub-sand filters. Sand would likely accumulate under the plate. Sand and UGFs do not get along.

– Wannabe mermaid

Lady Hobbs And to reiterate what has already been said…….. 🙂

You can’t use sand and UGF and you can’t have UGF with plants. People who use UGF generally use them in rock tanks with reverse pumps to push the dirt up and then other filters to remove what’s being pushed up. They don’t filter well enough when used alone.

Plants also thrive much better in potting soil.

steph0990 thanks guys!!

While I don’t agree that UGF sucks, I’ll get either an Aquaclear 50 OR a Tetras Whisper 70 along with my UGF and probably make a finer gravel.

Thank you for your help 🙂

toddnbecka Take the aquaclear rather than the whisper, you’ll be a lot happier in the long run. Check E-Bay, you can usually find a good deal on a used Aquaclear if you don’t want to spend the money on a new one.

Sandz Good luck Steph, but please remember that you 1) asked for advice and 2) admitted that you are a noob in this area… I strongly encourage you to embrace the idea of ​​using a UGF with plants rethink. They are NOT okay to put together. One way around this is to use slate rock to “pot” your plants in the tank. I have a friend with a 150gal who does this and it works fine.

ILuvMyGoldBarb I wanted to stay out of this one but decided against it as the OP deserves some accurate info.

Firstly yes you can certainly use sand with a UGF (how do you think people filtered early sea tanks?!?)

Second, yes you can have live plants with a UGF.

It all depends on the right setup. Of course you can’t just throw sand on a UGF, you need something to keep the sand from sinking in. A thin layer of gravel and a layer of nylon webbing will solve both of the problems you’re struggling with. You can’t completely cover the bottom of the tank with plants, but you can still keep live plants. You can also not use very fine sand. Something like an Estes Marine Sand would probably work just fine.

Is it the best form of filtration out there? No, but it’s far from outdated, it just requires the right knowledge to set it up.

Fishguy2727 Get an AquaClear.

What size tank is that? Remember that you need a filter that is at least twice the actual tank size.

Although some people use UGF with no problem, it’s much easier for people to just put a HOB there and not have to worry about it. If they neglect it, they can clean the filter and not risk spoiling the whole tank. I personally see no reason to use a UGF when there are so many simpler, more effective and less risky methods.

dbosman The same applies to the fact that plants can live well on UGF plates. Some of the roots will get through and under the slab, but if you don’t rip the plants out regularly, that’s not a problem.

Sucking debris into the gravel is good for a planted tank. It’s packed with nutrients. Most planted aquarium enthusiasts can’t siphon their gravel. Too many healthy plant roots. Malaysian trumpet snails are great for stirring up the substrate. These, too, can get out of control.

What’s bad about UGF filters is a problem that affects too many things. Lack of knowledge and salespeople making up answers when they don’t know what they’re talking about. Most people don’t really pay attention to their tanks. Set it up, top up the water when the filter gets noisy, buy new fish every few months to replace what has died, and complain in a few years when the aquarium crashes. Pointing out that the owner poisoned the tank by never changing the water will only make you unpopular.

Having been involved with aquariums for the most part over the past fifty years, I have had the opportunity to see several technology cycles. I have a 70 gallon tank with UGF panels with performance heads (and performance filters) and light blue epoxy coated gravel. My wife chose the color. None of my planted aquarium buddies like the gravel. The last massive plant removal included a 10 gallon tank full of seaweed, a 10 gallon tank full of various mosses, a 5 gallon bucket full of java fern, and several shoeboxes full of other plants. The money from the sale of the shrimp was paid for a nice batch of crystal red shrimp

There was once an old man in Michigan who raised and raised discus in large tanks with a sandy bottom and lots of pond plants. What he didn’t have were massive daily water changes or filters. People always said it wasn’t possible. He didn’t argue or try to prove anything. He simply bred and sold discus.

One area where UGF panels are making a comeback is in shrimp tanks. A UGF plate with a hob that draws water through the gravel is perfect for preventing shrimp from being sucked into the filter.

Lady Hobbs The big difference here is that this is a newcomer to aquariums and is trying to plant an aquarium for the first time. Very different from being an expert who knows about backup pumps and how to work around the problems of using a UGF. A much easier way is to just remove the UGF and use its sand because we all like moving our plants when we start this hobby.

They probably need to address their problem with additional filtering and plant lighting before doing anything else now. Is there no point in planting a tank without the right lighting?

steph……can you please give me more information, how big is your tank and what kind of lights do you have?

MCHRKiller IMHO the UGF gets a bad rap because people tend to forget it’s a filter and never clean its media…ie the substrate. It’s also very possible to use it with sand, but I would steer clear of fine sand and focus more on a finely crushed silica sand. These somewhat coarser-grained quartz sands can be absorbed very well and do not compact like many fine-grained sands. A roll of polyfiber placed on top of the UGF board before adding the sand would work best to prevent it from falling into the boards.

Would I put heavily rooted plants in the substrate of a UGF? No, the roots would be damaged by properly cleaning the sand, not to mention it would be much more difficult to keep it clean with these heavily rooted plants. These plants also require heavy substrate fertilization which would also be useless in a UGF as the ferments would be sucked away. You can grow plants like ferns, anubias, mosses and floating plants with very good success and keep your heavily rooted plants like swords and crypts in pots for easy care.

Using such a setup isn’t “wrong”, but there are undoubtedly better and definitely easier ways to get your desired setup. Many consider UGFs to be old technology, which they are, but that doesn’t mean they’re useless. It’s more work to keep a UGF working well than it is to keep a stovetop or canister running.

I would use sand:

http://www.substratesource.com/index.php?p=substrate&pn=NM0104

The Scrup FYI polyfilter will be 100% clogged in a year or two, possibly sooner in this application. Mine gets a nice impermeable barrier after about a month in my HOB’s, needs about 2-3 months in the swamp. This depends on the total surface area and flow rate, as well as the biological load.

Lady Hobbs How about a plastic shield….like a window pane?

toddnbecka I have used bulk filter media (blue/white bonded pad) to separate layers of crushed coral and black gravel on UG filter plates in some tanks. There are powerheads with Quickfilter cartridges (also filled with the same filter media or sponges) set up to run the plates in counter-current. Most of the dirt collects in the quick filters or the sponge filters (or canisters on the 55) which are flushed out during partial water changes. The layer of filter media in the 55 has not been moved in years and still shows no significant accumulation of debris. The 29er with the sponge filter has been disassembled and cleaned twice in the past few years, but it wasn’t because the filter media was laden with dirt or impeded the flow of water through the substrate.

MCHRKiller I have been using a UGF as extra filtering on my 100G for well over a year when housing medium sized SA cichlids…it wasn’t really all that dirty as a good gravel vacuum kept it clean. But that’s the whole key to a UGF…keeping the substrate/medium clean over the platters. It’s best to put what is on 2 sheets so you can easily remove half of it while stacking the entire substrate on the other side. That way it wouldn’t be such an ordeal if it had to be changed.

steph0990 aha sorry people haven’t been around to check my thread for a long time.

great ideas for using sand and UGFs..first of all i have a 40cm high tank..i have decided to use an aquaclear 70 as a filter with a sand substrate..it has been running for a few days now..will run it about another eek and 1/2 with no fish (I have extra stability and top fin bacteria supplement)

toddnbecka I use Aquaclear filters on several pools with ‘sand’ substrate and put sponges over the inlets to keep the impellers from being destroyed. Cichlids are particularly bad at picking up and spitting out sand and on more than a few occasions I have found it to have piled up around the bottom of the inlet sponge covers. The replacement penguin powerhead sponges work best IME, they are coarse enough not to clog too quickly.

sskwirl I have no problems in my cichlid tank. 125 gallons, sand, live plants and UGF. Now I have inverted powerheads that create some cool quicksand in some areas from time to time when my cichs come to dig, but they’re easily fixed with a big rock. I’ve been using this system for several years and haven’t had any problems with it or the dreaded tank crash. I do a pretty good job of keeping it clean and I have a canister filter too.

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With all the technological advances in the aquarium hobby, I thought it would be nice to take a look at one of the most rudimentary and long-lived devices in the industry – the bottom filter.

Background filters have a pretty bad reputation. They are sometimes considered a relic of aquarium history, but are they still usable? Some hobbyists swear by them and some hobbyists swear by them. How your tank performs with an undergravel filter depends on a few factors – setup and maintenance. Let’s take a look at some of the most common problems related to undergravel filters and explore some solutions.

The problem: They don’t work well enough. Some say bottom filters are inefficient in tanks with a lot of fish.

The solution: Proper setup is very important in filtration. This applies in particular to underground filtration. Using the right size and amount of gravel plays an important role in how well your filter will perform. To ensure maximum efficiency from your filter, you need to make sure you have at least 2 to 3 inches of gravel over the filter plate. The gravel should be of mixed quality, but make sure you don’t have anything so small that can slip under or through the grate. You also want the gravel to be evenly distributed across the soil. Because water flow follows the path of least resistance, an area with less gravel will receive more flow than an area with more gravel. This leads to a less efficient use of the entire filter plate. Another thing to watch out for is using large chunks of stone or wood laid flat on the gravel. These ornaments can restrict the flow across the area.

Another recommendation: Use compressed sand air vents instead of compressed paper air vents. Paper vents clog quickly. You should replace the air vents every month regardless of which ones you use, but the sand air vents work better over longer periods of time.

The problem: They are DIRTY! Many hobbyists have horror stories about the amount of dirt that accumulates under the filters over the years. Another complaint is that they are troublesome to maintain.

The solution: Fish waste and other debris is pulled down through a debris under the filter plate, making it easy to see why someone might think it was dirty. People assume that if you have undergravel filtration you shouldn’t vacuum the gravel because they think that would destroy or suck up the beneficial bacteria. Proper maintenance, however, will ensure that excessive litter and debris does not accumulate under the slab.

To keep your filtration running at peak performance, you should perform weekly water changes. Mentally divide your tank into quarters. Select a quarter of the tank each week and vacuum the gravel in that section. Go about half an inch deep into the gravel with your gravel siphon. This should remove a good amount of the dirt that settles under the filter plate while preventing the bacterial colonies from being completely wiped out. It should also allow the bacteria to recolonize the area before you need to vacuum the next section. If you follow this schedule, your undergravel filter should not accumulate excessive waste or produce nitrates in large quantities.

Simply put, undergravel filters have been around for so long because they work. The low-tech and simple device can be used successfully for years with proper maintenance. Keep your tank well stocked (don’t overload it), don’t overfeed, and keep water changes on schedule. You should have as much success with an undergravel filter as with the more advanced filtration techniques available on the market today. Give an underbody filter a try…with the right setup and maintenance, it can be a dependable and cost-effective tool.

Many Thanks,

craig