Pond carbon uses a process called chemical filtration which removes dissolved organics from your water garden. These organics can make the water yellow in color. Pond Carbon will remove colors, odors, medications and other impurities to help make your pond water clearer. It is recommended to use carbon on a intermittent basis. Pond carbon needs to be placed in a mesh bag to contain it. Once the pond carbon is in a bag, it can then be placed in a area of high water flow. Some recommended areas include: underneath a waterfall, a upflow waterfall filter,biofalls filter, canister filter or other types of pond filters. Each container of carbon comes with one mesh bag, a $4.95 Value Pond Carbon 5 lbs. PC5 Pond Carbon 9 lbs. PC9 ponddepot@msn.com Copyright - All World Rights Reserved Pond pumps, Pond Kits and Pondless Waterfall kits, Underwater Pond Lights. Aquaclearer Extreme bacteria and String Algae Buster and pond fish food. Pond Depot provides Do-it-yourself pond kits and Pondless waterfall kits delivered right to your home at great prices! Thank you for shopping at Pond Depot you online pond superstore!