AQUANEAT Aquarium Electric Sponge Filter for Fish Tank, with Pump, with 2 Extra Sponges, Middle up to 40GalBrand: AQUANEAT Color: black Features: Electric sponge filter with powerful motor, no need air pump; Just plug it in, it works Sponge filter provide both mechanical and bio filtration, also, the air infusion chamber produces minute bubbles which increase the oxygen solubility New Design: two media containers with ceramic ball inside, you can also replace this ceramic media with other media Comes with 2 spare sponges, put them in the filter box, please