Boyu bio sponge filter | sf-104 is simple internal filter works with the power of any air pump connected to it by means of a flexible hose. It can also be used as a prefilter for external filters or powerheads. Sponge filters provide a suitable mechanical and biological filtration, according to the size of the filter and the bio load of the aquarium. They are cost-effective as they consume only a tiny amount of power to pump the air needed. Supplying the water with much needed oxygen. Easy maintenance is made of foam sponge. Ideal for breeding, especially for discuses and other small fishes. Suitable for upto 250 litre tank. Note: requires an air pump to operate which is not included.