Each of Tech-CB Part A and Part B is half of a ionically balanced, complete calcium and alkalinity control system for all marine aquariums. When used simultaneously in equal amounts, the system will raise both the calcium and buffer level in the aquarium, and is phosphate, nitrate and gluconate free! Containing over 28,000 P.P.M. of cationic calcium, predominately in the form of calcium carbonate, Tech-CB will produce an ionic residual with the composition of natural seawater! Each 16 oz. Of Tech-CB will treat 1,900 gallons or 7,200 litres.