REPLACEMENT CARBON FILTER: Keeps aquarium water crystal clear – removes odors and discoloration.: Dense, dual-sided mesh filters debris and fish waste. Color coded to make it simple to remember which replacement cartridge size to purchase. Replacement filter cartridges are fully assembled and ready to use. Change monthly or sooner if needed. Made by Tetra Brand New in Box old design on box and faded from shelf wear Items are Brand New in Box never opened fits bio wheel 160 & 300
