Aquarium filtration information: The total picture

One of the most important parts of fishkeeping is also one of the easiest. Just like an air filter cleans the air we breathe, an aquarium filter cleans the water your fish breathe. It also helps keep your aquarium looking pristine. The best aquarium filters process three types of waste:

  • Solid waste is any type of dirt, particle, or debris floating in the water like fish waste and uneaten fish food. This type of waste is removed through mechanical filtration.
  • Dissolved waste is organic compounds, such as decaying tissue in tap water, and can cause odor and discoloration of the water. This type of waste is removed through chemical filtration.
  • Biological waste includes all unwanted contaminants, like ammonia and nitrate, which have to be biologically processed rather than filtered. This type of waste is removed through biological filtration.

Aquarium filter types

Power filters typically use disposable cartridges and hang on the back edge of your aquarium.
Internal filters are primarily made for smaller aquariums (under 20 gallons) and are placed inside the aquarium to provide water movement.
Canister filters provide excellent filtration for larger aquariums or aquariums with a lot of fish. They are usually placed in a cabinet or stand beneath the aquarium.

Filter maintenance

  • First, always make sure there is water in the pump chamber. If you don't, the filter will pull in air instead.
  • Keep an eye on how much water is in your aquarium—most filters need the water level to be about one inch from the lip of the filter.
  • Make sure your bubble walls and/or air stones are not directly under the intake tube. If bubbles go up the main tube, it will cause a rattling sound and may stop your filter from working.
  • Always use gravel in your aquarium instead of sand. Sand can cause problems with the impeller, because it gets between the magnetic impeller assembly and the energizer, preventing it from turning. If you do have sand, a good option is to purchase a mesh net from your local pet store, or even use a piece of panty hose, and place it on the strainer. Your filter will pull out the waste, but it won't pull up the sand.
At Tetra, we offer fish owners a wide selection of filtration systems to help them maintain cleaner water and healthier fish. If you have any questions or need help troubleshooting a filtration issue, please feel free to contact one of our friendly TetraCare experts. We're happy to help.

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