The Tetra Whisper Power Filter for aquariums offers quiet, 3-stage filtration for clean water and healthy fish. Dual-sided mesh catches debris and fish waste in its dense, fibrous network, then Ultra-Activated carbon provides chemical filtration by absorbing odors and discoloration. Biological filtration is provided by the Bio-Foam, which creates a large, three-dimensional area for cultivating aerobic bacteria, which eliminate toxic ammonia and nitrite. No moving parts means long-term reliability. Uses Stay Clean technology to help keep your aquarium clean, clear and healthy, reduce buildup on aquarium glass and bind small dirt particles to make them easier to filter. This filter uses easy-to-change Tetra Whisper Bio-Bag Cartridges, includes 2 size large filter cartridges (replacements sold separately). Filter cartridges trap particles floating in your aquarium. The Tetra Whisper Power Filter 30-60 treats aquariums up to 60 gallons (330 GPH).