Tetra Whisper Bio-Bag Large Filter Cartridges for Aquariums, 12 Count, Unassembled, Fits Tetra Whisper Fish Tank Filters 10-30 Gal, 20-40 Gal, PF-20, 30, 40, 60, IQ 20, 30, 45, 60

[gallery] Tetra® Whisper® Bio-Bag® Disposable Filter Cartridges keep aquarium water crystal clear and remove odors and discoloration. The dense, dual-sided mesh catches debris and fish waste. Ultra-Activated® carbon absorbs odors. Use these replacement filter cartridges in your Tetra® water filter – each package is color-coded to make it simple to remember which size to purchase. These replacement filters are easy to assemble and easy to replace. Clear water made simple. Replace a clogged Bio-Bag filter cartridge when there is reduced water flow out of the filter. For best results, change your filter cartridge monthly or sooner if needed. Size large. Choose the medium size filter cartridge...