Partical charming Aquarium pretty cosy Biochemical 2830 Air Sponge Filter Fry Oxygen Shrimp Breeding by DragonElf Sponge filters provide both mechanical and biological filtration Simply install an air line into the unit and provide both aeration and filtration for your fish. Aerobic bacteria colonize the sponge providing a bacterial substance to facilitate the nitrogen cycle addition, the sponge traps larger waste particles mechanically cleaning the water without trapping baby fish. They are useful for as breeding filter or as secondary filter. Or they can be used as pre-filtration unit by fitting to an external or a top filter. The bio-sponge filters are designed and constructed with quality materials that will outlast any other sponge filters on the market. The sponge is designed and constructed with the multilayer principle and the largest surface area possible with no clogging. The sponge material is easy to clean. Quiet operation The air diffusion chamber produces minute and large number of air which increase the oxygen solubility in the water. They are useful for as breeding filter or as secondary filter or they can be used as pre-filtration unit by fitting to an external or a top filter.