1. Fine filtration: The fish tank biofilter provides mechanical and biological filtration, which captures debris or waste without sucking away your fish, keeping the fish tank clear. 2. Circulation filtration: The aquarium filter cartridge uses pneumatic filtration, flowing through the biochemical cotton and hollow quartz balls, effectively filtering and accelerating water circulation. 3. Quiet and aerated: The aquarium biofilter uses pneumatic drive and will not interfere with your daily life. Press the sponge in the water tank to fully absorb the water and let it sink to the bottom. 4. Easy to clean: Each aquarium filter can be easily disassembled for cleaning. Rinse with aquarium water every 2 4 weeks. Do not use tap water to clean! 5. Application: The fish tank bioball filter is suitable for breeding and raising various ornamental fish, shrimp or fry. It is also suitable for various fish tanks and aquariums.