How To Make An Undergravel Pond Filteration System

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Look:

Don't let anyone tell you undergravel filters tin't be an constructive filtration option for your tank.

When done right, they can be POWERHOUSES for stabilizing a healthy aquarium.

Granted:

The traditional undergravel filter setup method is straightforward:

Plates on bottom.

Gravel on superlative.

Water pulled down into the gravel bed.

BUT…

There are some pretty major drawbacks to this setup (which is partly why they have fallen out of favor in recent years).

Gunk gets trapped in the rocks and under the filter plate. Not only is information technology difficult to clean, only really, this can be a very dangerous problem – especially if non cleaned very frequently. Equally in, all. The. Time. These pockets can go anoxic and nasty disease-causing bacteria can course in these areas, leading to sick fish. Fifty-fifty if you lot vacuum out the gravel often, you withal can have all this debris lodged nether the actual plates that can't come out without a deep cleaning – sometimes necessitating a tank tear-downwardly.
Small gravel poses a choking risk for some fish like goldfish. Bigger or developed goldfish peculiarly are decumbent to getting "rockitis" where the gravel actually gets lodged in the back of their throats, blocking their ability to eat and causing other symptoms like lethargy and foreign mouth movements.
Hard to grow plants in directly. Plants tin can grow roots into the filter plates and restrict the water flow through the filter, destroying the effectiveness of your filtration. If you want rooting plants it'due south recommended to continue them in something like a glass constitute jar.

I'm non saying never ever do it this fashion or it's the end of the earth if you practice.

Only I think at that place are some better means that will make your life easier and keep the risks down for your fish.

My motto?

Fishkeeping should be as simple as possible.

So today I'm going to share the top 2 ways to set up an undergravel filter that overcome both of these problems – and brand your biological filtration MUCH more efficient in the procedure!

Related Postal service: Do Goldfish Demand Gravel?

Tabular array of contents

How to Fix Up a Safer, Easy to Clean Undergravel Filter for Your Fish Tank
- The Sand Cap Method
- The Contrary Menstruum Method
Advantages of Undergravel Filters
- Quiet
- Invisible
- Huge biological footprint
- Substrate Aeration
Conclusion

How to Set Up a Safer, Easy to Clean Undergravel Filter for Your Fish Tank

I'm giving you the ii best methods I know of.

There may exist others I oasis't tried that are merely equally expert or even meliorate.

As well:

Don't be afraid to get creative and experiment if you lot desire.

For what it's worth, I really like the Penn Plax line of undergravel filters as they can exist customized to fit almost any dimension of tank.

penn plax undergravel filter

You lot can likewise slice together several smaller sizes if your aquarium has a unique footprint.

Whatever works for you.

You tin employ the setup designs below alone or in conjunction with another kind of filter.

The Sand Cap Method

This is thought combines the benefits of sand (does not trap muck similar gravel) with the efficiency of undergravel filtration.

I recommend using CaribSea aquarium sand, the Crystal River style.

Out of all the sands I've tried, this one works the best.

Why?

The grain size is much larger than boilerplate sand merely yet small enough to prevent fish choking while having the debris sit on top, patiently waiting to be vacuumed.

I big advantage of this method is you don't take to deal with plants rooting in the filter plates, which is a big problem for growing plants with traditional UG filter setups. Due to the strategic placement of the polyfiber barrier, this method is ideal for keeping rooting plants.

I highly recommend calculation some heavily rooting plants equally it volition keep the substrate aerated and help lock downwardly the gravel-blazon media under the sand for those with digging fish.

Not all plants enjoy soil aeration, only some like Amazon Swords actually do.

The roots cannot go through the barrier and block the catamenia – only the h2o can.

The barrier is non thick enough to serve as mechanical filtration, and even if it were it is far down beneath the layers of sand and gravel-blazon media. This means it does non demand to exist replaced continually.

Place your assembled undergravel filter plates on the make clean, blank lesser of the aquarium.If your tank is already set information technology is a adept thought to do a thorough vacuum and water modify. You will demand an air pump and airline tubing to run the airstones in the filter. I use the double outlet airline pump as you lot don't take to T off the airline tubing and yous only need to use 1 outlet to run information technology.
Cut a piece of thin polyfiber padding to fit over the surface of the plates. This will ensure no fine debris or sand can work their fashion down underneath the plate and go nasty over fourth dimension. I used an Imaginarium thick polyfiber pad torn iii thinner layers and spread them on the filter plates, snipping a slit in the fiber where the uplift tubes connect. Information technology's ideal because the construction allows a lot of h2o flow while preventing sand and debris from entering. You don't want to utilise something that volition break downward over time, like a cotton textile.
Pour a 1/2-1″ layer of gravel, pre-soaked Seachem Matrix or crushed coral (for hardwater fish like cichlids) over the polyfiber. This will help with h2o circulation as well as provide boosted surface surface area for biological colonization. If yous use crushed coral or some other porous substrate, you can also provide an expanse for denitrification (aka nitrate reduction) to occur which would not happen with gravel. On top of this layer (optional merely not manditory) yous tin can place a layer of mesh or gravel tidy to prevent this layer from intermingling with the sand.
Cascade a 1.5-2″ layer of sand over the gravel. If you take digging fish you will want to apply almost 2″ to foreclose them from agonizing the gravel underneath.

Some tips:

Virtually UG filters come up with lilliputian carbon inserts you lot can put on the tips of the uplift tubes.

If you're similar me, you find this unsightly.

Part of why I love Undergravel filters is because they are just about invisible, and I don't want distracting little black squares in the tank (third globe problems, right?).

So where exercise yous add other kinds of media (maybe Phosguard, Purigen, Algone, active carbon, or otherwise?)

With this particular setup it isn't actually that easy – equally in, pretty much incommunicable – to push aside all the stuff on summit of the filter plates and coffin your packets of chemical filtration like it would exist with a regular undergravel filter setup.

And if yous have plants rooting – forget about it.

But at that place'southward a workaround:

I apply this lilliputian internal ability filter merely big enough to put my chemical filtration in, stuck behind a rock and plants. It doesn't have to be huge, as it'southward non functioning for biological filtration (you are more than covered on that!).

Yes information technology gives you another black cord to deal with, but hopefully your tank is planted plenty that the stems and leaves can conceal it.

The Reverse Flow Method

Reversing the flow has some major advantages (source).

Here's how to do it:

Identify your assembled undergravel filter plates on the clean, bare bottom of the aquarium. No demand for the airstones here.
Pour a layer of gravel or larger porous filter media (such as Seachem Matrix, Swimming Matrix which is a bit larger than Seachem Matrix, or Hydroton). You can also use larger river pebbles, though these may restrict the water flow more than and won't support nitrate reduction.
Utilize a submersible powerhead to force water down the uptake tubes. This is what reverses the flow and pushes water up through the substrate rather than forcing waste product down. Pumping water through the substrate upwards keeps it free of mulm-buildup, which can cause deteriorating in water quality.
Install a prefilter on your powerhead to prevent debris from beingness pushed by the powerhead underneath the filter plates. This is really a must or you will end up having the same trouble as a regular undergravel filter setup.

Information technology'southward a proficient idea to supplement this method with an airstone, sponge filter or HOB filter for aeration and surface movement.

Bonus:

Connect information technology to a canister filter packed with mechanical filtration media to purify the water first before it sends the period downward the UG filter tubes from the outlet.

Hello, sparkling clean water!

goldfish gravel substrate — Image credit: Pixy

Advantages of Undergravel Filters

Tranquility

Bellyaching by loud sputtering, gurgling, trickling or dripping from other kinds of filters?

The just noise merely about will exist coming from your air pump vibrating (if you use one).

If you work in an office or want a serenity tank in your room this tin be a big perk.

Invisible

Just about every filter out there is an ugly intrusion into your beautiful aquarium scene.

There's almost no way to totally hide near of them.

With Undergravel filters, you integrate the filtration so closely into the aquatic surroundings there is almost no transition.

Huge biological footprint

Y'all tin can't vanquish the surface surface area the size of your aquarium's footprint.

End of story.

Substrate Aeration

Prevents bad anaerobic forming in the substrate when set using the methods described to a higher place – score!

Information technology's okay to go heavier on your layers of substrate since yous are getting oxygenation happening.

Conclusion

I hope this postal service sparked your interest in the possibilities of filtration with undergravel filters.

What about yous?

Have you tried them, and what accept been the results in your tank?

Featured Image Credit: PDPics, Pixabay