hygger Aquarium Double Sponge Filter: Upgraded Sponge Filter with Larger Filtration Area, Come with Extendable Clip, 2 Spare Biochemical Sponges, Bioceramic Balls, for Freshwater Saltwater Tank - SBrand: hygger Color: Black Features: Mechanical and Biochemical Filtration: Powered by air pump, hygger aquarium sponge filter use the rising air to generate a strong adsorption force on water through the sponge and combine with bioceramic balls to effectively adsorb and decompose impurities in water, achieving the purpose of filtering and purifying water quality Upgraded Filtration: This sponge adopts a vertical stripe design. 1. It has a larger