NT Labs Marine Supercarb is super active filter medium, it removes organic molecules, colour taint and significantly enhances water clarity in marine aquariums. Use to remove residues of treatments from water. NT Labs Marine Supercarb is of the highest grade carbon for ultimate purity, it does not leach any phosphates or heavy metals and is suitable for the most sensitive reef aquariums. Place NT Labs Supercarb directly into a high flow area within your filtration system for optimum results.