Carbon Premium Dupla Marin activated carbon pellets detoxify the water in aquaria, preventing yellow casts, removing enduring organic pollutants, binding residues of medication and algicides and decomposing protein compounds. In salt water the corals toxins or urticanttoxins are absorbed. Fast-acting due to the extensive surface ( approx. 950 cm2 per gram ) Made from high grade hard coal, activated in a highly complex process. Includes mesh bag.