Aquapapa 4X Dual Bio Sponge Filter For Betta Fry Aquarium Fish Tank Up To 30 Gallon (Ship From Ca Usa) (Dual Sponge Filters 4-Pack)

Provide both mechanical and biological filtration. Simply install an airline 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. The sponge traps larger waste particles mechanically cleaning the water without trapping baby fish. Product dimensions: 5.0 L x 1.8 W x 5.5 H; sponge dimensions: 1.8 D x 3.0 H. 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. Max tank size up to 30 gallon. Package includes: 4 of Sponge filters.