Cascade presents the Pro-C Aquarium Canister Filter Media Bags with Activated Carbon by Penn-Plax. Along with providing a compact and easy-to-handle design the nylon mesh filter bags help create a simple solution to aquarium canister filter media replenishment. In addition to trapping loose particulate matter these Activated Carbon filled bags help to reduce harmful chemicals toxins foul odors and to clear up discolorations from your aquarium’s water. They help keep water inside your tank crystal clean! Shop Penn-Plax for All Your Pet’s Needs: Penn-Plax is a manufacturer and distributor of top quality pet supplies who specialize in creating excellent pet products for animals both great and small.