Types of Aquarium filters:
Overhead /Submerged power filter – This type of filter has a high-powered pump to push and recycle aquarium water through a canister containing filter media (activated carbon, sponge). Basically the canister can either be on top (overhead filter) or submerged inside the aquarium itself (submerged power filter) and both types work well to treat high volumes of water. However, a word of caution when using this type of filter is that always ensure that the filter is not oversized until it creates heavy turbulence in the water that will make the fish difficult to maintain balance while swimming.
Box filter – A box filter is a simple assembly in which there’s a box with a compartment containing filter media and basically it needs an aquarium air pump to drive the water through the media. It works by creating a suction flow due to the movement of air bubbles exiting through the outlet line and thus, drawing together with it water from the surrounding area through the filter media. However, this type of filter can only treat small volume of water.
Undergravel filter – The undergravel filter utilizes the gravel bed as a filter media. Similar like box filter, the water is drawn from the surrounding area through the gravel bed using suction created by an air pump. If you happen to come across aquarium whereby you can see air bubbles rising from the aquarium bed, then you will instantly know that it is utilizing undergravel filter. One advantages of using this type of filter is that it creates a magnificent view of bubbles rising from the gravel bed and is able to provide higher volume of filtration capabilities. However, one disadvantageous is that it will require a lot of time during maintenance to clean the filter because basically you have to move the fish out and digging everything including the gravel bed. With the large filtration surface area, it can last months without clogging and still able to filter effectively but beware, undergravel filters are known to harbor huge buildup of ammonia gas deposit trapped between the gravels.
Finally, which aquarium filter suits you best will very much depend on your size of aquarium including budget and never ever assume that once you have a filter in place, you don’t have to worry about the aquarium maintenance anymore. Please remember that even though you can have the best aquarium filtration system in place, nothing beats the importance of performing regular water change and conducting periodic water parameters checking.
Other types of aquarium filter: Trickle Filter and Diatom Filter