Aquarium Filtration 101

Filtration is necessary for any aquarium, sometimes looking at all the options available can be overwhelming. We will help you discover which filter would work best for you.

There are three main categories of filtration in the aquarium hobby, these include mechanical, biological and chemical. Mechanical is used for removing solid particulates from the water, biological filtration uses the nitrogen cycle to break down ammonia into less toxic nitrogen compounds, and chemical filtration removes waste via binding molecules before they have chance to break down in the aquarium. Different filters use these types of filtration differently and we are here to help you decide which type is best for you.

First you have sponge or under gravel filters. These filters work via biological filtration, tried and true because you can't doubt biology.

  • Under Gravel Filters - usually either air or powerhead driven. As water is pulled downward through the gravel, nitrifying bacteria are breaking down ammonia (fish waste or uneaten food) into more safe forms of nitrogen. These work best when a deep substrate bed of average sized gravel is used as this promotes optimum water flow.
  • Sponge filter - using the same idea as under gravel filters, the nitrifying bacteria is just primarily stored in the sponge. These are best used for fish that do not handle flow well, especially axolotls and bettas.

Then you have multi-stage filtration like in hang on the back and canister filters.

  • Hang On Back - these pull water up through an uptake tube and then filter through various medias in a box that hangs on the back of the aquarium. The most popular style aquarium filter. Gives you the ability to customize your chemical filtration.
  • Canister Filter - pulling up water through an uptake tube positioned in the aquarium, water is then filtered through various medias in a canister that is located underneath the tank. These are by far the most customizable as far as foam and other medias you can put inside them. They are also our employees favorite style to recommend to customers.

Lastly, there are all-in-one systems. These are the most streamlined and clean looking options.

  • All-In-One Systems - filtration is built into the back of the aquarium typically, and are so sleek looking. Everything is built in and they are extremely easy to maintain! By far the most popular option for people just getting into the hobby or looking for desktop tanks.

Check out the full length version of the filter breakdown below!

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