Highly-concentrated ionic calcium solutionIncreases the concentration of calcium in marine aquarium water to provide corals and other reef-building invertebrates with one of the most important elements required for growthIs ionic rather than chelated, and contains no unwanted organic material such as EDTA, gluconate, or polygluconateOver 50% stronger than most competing productsFree of phosphate, silicate, and organic materialFormulated by a marine scientist