Tetra® Bio-Bag® Filter Cartridge with Stay Clean™ technology keeps aquarium water clean and clear. This filter’s dual-sided floss sleeve removes dirt and debris and contains Ultra-Activated® carbon to remove odor and discoloration. Its integrated design also includes a Stay Clean tablet that dissolves steadily over time, leaving you with healthier water and cleaner aquarium glass. Stay Clean technology helps reduce buildup on aquarium glass, bind small dirt particles to make them easier to filter and stabilize pH levels to prevent crashes – meaning easier aquarium maintenance for you. Tetra Bio-Bag Filter Cartridges are compatible with Tetra Bio-Bag aquarium filters – each package is color-coded to make it simple to remember which size to purchase. These replacement filters are assembled and ready to use for your convenience. This large-size filter cartridge fits Tetra Whisper®10i, 20i and 40i Internal Filters, Whisper PF10, PF20, PF30, PF40 and PF60 Power Filters and Whisper IQ10, IQ20, IQ30, IQ45 and IQ60 Power Filters. For best results, change your filter cartridge monthly or sooner if needed. Since 1951, Tetra has developed the world’s most comprehensive body of fish food knowledge, and fishkeeping enthusiasts have looked to the brand for products and solutions that add ease and beauty to their home. Whether you're an experienced hobbyist or just starting out, Tetra has everything you need – from a large variety of quality fish food and innovative equipment to test kits and decor. REPLACEMENT FILTER CARTRIDGE: Keeps aquarium water clear – removes odors and discoloration and helps reduce buildup on aquarium glass. STAY CLEAN™ TECHNOLOGY: By maintaining healthy pH levels, creates easier maintenance for healthier fish. FITS TETRA® WHISPER® AQUARIUM FILTERS: Color coded to make it simple to remember which cartridge size to purchase. CONVENIENT: Pre-assembled, ready to use and easy to replace. USAGE: Change monthly or sooner if needed.