Bio-Chemical Sponge Filter This simple internal filter operates with the power of any air pump connected to it via a flexible hose. It can also be used as a pre-filter for external filters or powerheads. Sponge filters provide suitable mechanical and biological filtration, depending on the filter size and the amount of biological load in the aquarium. They are cost-effective as they consume only a small amount of energy to pump the necessary air. Diameter: 7.5 cm Height: 9.3 cm Height including exhaust pipe: 19 cm (the exhaust pipe can be shortened by cutting)