Benefits and Uses of Biological Filtration in Aquarium / Why Bio Filter is Very Important for Fish Tank:

Aquarium filtration is divided into 3 types: Mechanical, Biological & Chemical filtration. Biological filtration is the most crucial of all types of filtrations. Lack of biological filtration is responsible for the death of most of the fish. Chemical filtration is not necessary & aquarists usually avoid them. Mechanical & biological filtration are the important functions performed by every filter. A foam or sponge is used as a mechanical filtration media that stops fish waste, uneaten food & other debris, & allows water to pass through it. Biological filtration chamber contains bio media that allows heaps of useful bacteria to grow on its surface. This bacteria is responsible for consuming toxic chemicals released from fish waste & other decaying matter, so bio media removes germs from toxic water & allows clean water to flow back to the aquarium.

Benefits and Uses of Biological Filtration in Aquarium
Benefits and Uses of Biological Filtration in Aquarium

Benefits and Uses of Biological Filtration:

  • Biological filtration can remove heavy metals from the water.
  • Biological filtration breaks down dangerous ammonia into less dangerous forms. Ammonia is broken down into nitrites & nitrates. Nitrates are less toxic than nitrites & ammonia.
  • Nitrifying bacteria wipes out nitrites & ammonia from the water.
  • Ordinary bio media can’t remove nitrates from the water. But some bio media like ceramic noodles can even wipe out nitrates. Ceramic noodles have many tiny little pores on its surface & there is one large hole in the center that goes through the entire length of the ceramic rings.
  • Bacteria that remove nitrates from the water are known as Denitrifying bacteria. This bacteria usually grow in oxygen free places such as inside tiny little pores of ceramic noodles. So, clean water with no dangerous chemicals flows back to the fish tank after passing through ceramic noodles.
  • Biological filtration is used to offer a clean & healthy environment for fish, live plants & invertebrates.
  • When a plant dies in water, & if it is not removed, it swells & pollutes water. This pollution could be toxic to the life of aquarium inhabitants. Biological filtration is responsible for absorbing the decaying matter released from dead plants.


  1. I always keep multiple sponge filters going in the sump pf my saltwater aquariums. You never know when you may need to setup a new hospital or quarantine tank. You basically have an "instant tank" ready to go at a moments notice. I do not keep an airline hooked up to the sponges as I feel it is not necessary, so its simple and easy to do. Actually this past week one of my peppermint shrimps released her larve into my QT tank i had for the shrimp I just purchased. I was able to move the shrimp over to a new tank and keep the larve separate. I would not have been able to do this if I didn't have an extra sponge filter in the sump of my main tank. Also, like you mentioned, ceramic media is also a very good filtration media to use. I keep Marine Pure Spheres in my sump as well just in case I end up using all of my filter sponges and I need to setup yet another tank for some reason.


Post a Comment

Previous Post Next Post