Red Sea NO3-PO4-X Nitrate & Phosphate Reducer 500ml is a complex carbon based product which will reduce and maintain nitrates and phosphates in the marine aquarium. This unique blend of carbons is used by nutrient reducing bacteria. The carbons are utilised by different strains of microorganisms whilst ensuring the specific carbon - nitrogen - phosphorus ratio is maintained for each stage of the process. The fine control of nitrate and phosphates in the aquarium when dosing with Red Sea NO3-PO4-X guarantees the gradual change and accurate maintenance of nutrient levels, preventing any shock or starvation to corals or its zoozanthellae algae. Unlike home made recipes, when used correctly, Red Sea NO3-PO4-X will maintain all micro fauna that are beneficial to the reef, whilst reducing nutrients which cause algae. Monitor with Red Sea Algae Control Test Kit to ensure optimum dosing. 500ml bottle.