Maintain healthy pH levels in your tank with Tetra BIO-Bag Aquarium Filter Cartridge. This filter features duel-sided floss that removes dirt and debris from your aquarium to keep it clean for your underwater buddies. It provides four stages of filtration with ultra-activated carbon that removes odors and yellow discoloration. Compatible with BIO-Bag filters, Tetra BIO-Bag Aquarium Filter Cartridge will keep your tank looking and smelling good.Why We Love It:Filter helps maintain healthy pH levels in your aquarium.Removes dirt and debris with duel-sided floss.Removes odors and yellow discoloration from your tank.About TetraTetra aquarium products are dedicated to helping seasoned hobbyists and beginners alike to enjoy a successful, life-long aquatic experience. Our complete line of Tetra nutrition, water care, filtration and aquarium products help make fishkeeping accessible to all hobbyists so they can benefit from its rewards.