What is the best filtration system for a saltwater aquarium?
For a saltwater aquarium containing only fish, it is possible to use a variety of filtration systems. The system you choose will depend on the size of the aquarium and the amount of fish you wish to keep. The best filters are a sump tank system or a canister filter. Canister filters consist of a small canister that fits below the aquarium containing a tray system for the addition of media and a variety of ceramic products for chemical and biological filtration. The canister contains a pump that pumps the water down into the canister and back up into the aquarium. Canister filters use both mechanical, chemical and biological filtration. The main disadvantage of canister filters is that they have to be cleaned frequently and they can be difficult to clean. They are also not a good choice for large aquariums as they limit the amount of media that can be added to the system. When using the canister option you will also be limited to using a hang on the back or close loop protein skimmer, which can be unsightly.
Sump filters are generally considered to be the best filters available for saltwater aquariums. They consist of a large container that fits underneath the aquarium which as a benefit will increase your overall water volume making stability of many parameters easier to achieve. There are several different types of sump filters available, and most use some combination of mechanical, chemical and biological filtration. Sump filters are a good choice for mid-sized and large aquariums, but should always be considered on all saltwater aquariums if the space and system allows for one.