Calcium Calcion is a highly-concentrated ionic calcium solution designed for marine aquariums to boost the growth of corals and reef-building invertebrates by increasing water calcium levels. It contains over 50% more calcium than most competing products, making it an efficient choice for aquarists looking to maintain optimal water chemistry without unwanted organic materials like EDTA or gluconate that can interfere with other water parameters. This product is ideal for those managing reef aquariums where the rate of alkalinity depletion varies depending on stocking density and lighting conditions.