What are the best filters for a small freshwater aquarium?

What are the best filters for a small freshwater aquarium?

Marc Grover (Professional Aquarist) gives expert video advice on: Generally, how do filters work in an aquarium?; What are the best filters for a small freshwater aquarium?; What are the best filters for a large aquarium? and more...

When you're doing a small tropical freshwater aquarium, you want to start with the biological filtration. The number one method for me, in my opinion, is to use an under gravel filter and there are ways to make that function whether you are using a power head or an air pump. Then, you can get away with just that although you're tank typically isn't as clear as you might like it to be. You can then augment that filtration with either a hang on the back or a canister filter that sits underneath the aquarium, and that will accomplish both the mechanical water polishing filtration and it will take some other toxins out with chemical filtration, namely carbon or other absorption resonates. A lot of times people will try and cut corners and buy a prefabricated kit. Most of the time it is totally skipping or really downplaying the biological aspect of the filtration and focusing on the make the water clear for the viewer filtration. While that's a great sales point, it doesn't work in the long term for your fish because it really ignores the eco system basis of keeping your fish alive which is the biological aspect of the filtration system.