Best Sponge Filters For Small Fish, Quarantine, Breeding And Fry Tanks

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Sponge filter is an easy-to-use aquarium filter that is never suck up any baby fish and efficient in what they do to keep small fish like Guppies or Neon Tetras happy and healthy. Because its gentle flow rate, sponge filter is also the best aquarium filter for quarantine, breeding or fry tanks. Although they have got a very simple design and are dirt cheap, they can well perform both mechanical and biological filtration in your aquarium.

Best Sponge Filters For Small To Large Aquariums

Simple Constructed - Value for Money
  • Great Filter for Bettas or Small Fish
  • Cheap filter
  • Clearer water
Small Sponge - high quality
  • provide both mechanical and biological filtration
  • Absolutely fantastic product
  • Simple
Complete Reef Package - Money Saver
  • Provides the ideal location for bacterial colonization.
  • Extremely excellent water filtration
  • Super Efficient
Enormous Filter - Recommended
  • Sponge filter is great
  • Make tanks clear
  • Excelllent biochemical filtration.
Soft Sponge - High Quality

How Do Aquarium Sponge Filters Work?

The way a sponge filter works is very simple and need to be powered by an aquarium air pump (buy separately). Air tubing is placed in the center of the sponge blowing the air from the air pump out which makes a pressure pulling water through the sponge. By this way, any floating debris in the water will be sucked into the sponge leaving your aquarium with the great looking water.


Solid wastes are trapped by the sponge that allows manual removal once changing water, some are used as the food source for bacteria to colonize. Don’t worry because these friendly bacteria processes the toxins produced by the waste and decaying matter into less harmful nitrates which can be removed during weekly water changes.

The flowing water and aeration from the air pump not only provide the aeration for the fish but also help the bacteria quickly build up on the surface of the sponge. This procedure is called as the maturation of the filter. When your sponge filter is matured, courtesy of the beneficial bacteria will be found present on the sponge.

A functional sponge filter is not fully established until it’s about 6 weeks old, this can be reduced if you take a virgin sponge and place it into the gravel of a long established fish tank , give it a squeeze and then leave in there for 24 hours. This can greatly speed up the maturity process as its absorbing friendly bacteria from the other fish tank.

The missing of the sponge filter is chemical filtration that traps organic mater leaving your aquarium with the clear water. However, this type of filtration isn’t too necessary for a small fish tank with regular water changes and the truth is that people like to replace it with some more biological filtration.

Big Advantages Of Aquarium Sponge Filters

  • Air powered

    Sponge filters are powered by air pumps which is good because this is doing two jobs with one product, not only does the air pump pull water through the sponge it also aerates the water and keeps it moving 24/7.

  • Slowly but surely

    All brands work on the same principle; water passes through the sponge where it is cleaned both mechanically and biologically.

  • Perfect small fish tank filter:

    Big powerful filters can really harm small or fry fish and even kill them by sucking them into the propellers, this can’t happen with sponge filters because they are only air powered. Now other than not harming fry it’s also a live food banquet for the fry to feed from, all the bacteria growing on it really promotes micro organisms to grow which are the best food for new born growing baby fish.

  • Super cheap!

    As you can probably tell from just looking at them they are really inexpensive to buy, and they can’t break. Sure there not the best looking filters but they are 100% reliable and super easy to use, simply connect it to your air pump and away you go.

  • Easy cleaning 

    To clean the sponge filter, just remove the sponge and give it a couple of squeezes in a bucket filled with the old aquarium water (NOT tap water) to remove the large debris but not kill the helpful bacteria.

  • Overfeeding fixers

    We have all made the mistake of overfeeding our fish and the best way to clear your tanks water is by popping in a mature sponge filter full of friendly bacteria, within 24 hours your water will be back to normal and crystal clear.

  • Unlimited shapes and sizes

    Sponge filter come in a endless number of shapes and sizes to fit in any tank size, it is worth noting that the bigger surface area your filter has the more bacteria that grows which then means it can deal with more fish waste. Simple rule is the bigger the surface area the great its capacity.

Which Fish Tanks Need To Use A Sponge Filter?

For breeding and fry aquariums: If you are into breeding fish you have no doubt have heard of this type of filter before. The benefits of using a sponge filter with baby fish are threefold:

  • Firstly, they provide the good filtration and aeration for caring the baby fish,
  • Secondly, they cannot trap tiny fry as the suction i spread over the entire sponge surface,
  • Thirdly, they become a banquet of microbes when mature which are perfect first foods for many fish.

For Guppies tanksKeeping Guppy fish is a great hobby and things can be made even easier with the help of sponge filters in your fish tank. Guppies are not the dirtiest of fish to start with but like all living things they do produce waste which needs to be taken care of and not just left otherwise your fish will die from poor water quality.

For other small aquariums with small fish and Betta tanks that hate the turbulent water in their houses.

Top Editor's Choice on Sponge Filter

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