COVE Bio-Calcium is one of the important elements in the growing of coral and coral bone. When the KH value is maintained at 7-10DKH in the reef aquariums, coral can easily absorb the bicarbonate ion and converts it into carbonate ion, then combines with calcium ion, thus generating calcium carbonate bone needed in the growth. The higher the KH is, the faster the calcium consumption will be. The usage of COVE Bio-Calcium additive with high purity can effectively increase the calcium content in reef aquariums and provide essential calcium for the growth of coral and other organisms, leading to healthy growth of coral and other organisms. The combination of rational calcium content and stable KH value is one of the most important factors of healthy reef aquariums environment. COVE Bio-Calcium additive with high purity has mild and stable formula and exerts no impact to the reef aquariums system.