DrTim's Aquatics Carbon is a super efficient superior activated carbon made from bituminous coal that is phosphate free. Its shape allows effective water flow and maximum contact. DrTim's Aquatics Carbon will remove organics, colors, smells, metals and acids from your aquarium resulting in crystal clear pure water. Comes with our Standard 8" x 6" Mesh bag w/Zipper 1,000 micron size refillable media bag.