with a airlift system, super biochemical sponge filter features silent operation, and has an excellent filtering effect while oxygenation the water, the social developed foam materials supports the colonization of bacteria, allowing for mechanical filtration in addition to biological filtration(filter media pack included),which will break down harmful waste, ammonia and nitrite material, resulting in a cleaner living environment for your fish, particular they are useful for as breeding filter or as any size aquarium setup.