Canister filters are capable of Mechanical Filtration, Biological Filtration, and Chemical Filtration. This includes a combination of filter pads, sponges, ceramic rings, bio balls and activated carbon. The filtration media will need to be changed regularly for your canister filter to function at its best. Aquatop specializes in powerful, yet affordable Canister filters with UV Sterilization. We also offer genuine OEM replacement media and parts which guarantees maximum performance for the life of our products.