Red Sea Fish Pharm ARE22023 Reef Foundation Buffer Supplement-B for Aquarium, 500ml Reef foundation B is a complex of carbonate and other buffers present in seawater that maintain proper alkalinity and pH Calcium, magnesium, strontium and carbonate are the basic foundation elements of coral skeletons All of these elements need to be available in balanced proportions for coral health and growth Includes a convenient measuring cup for easy dosing Available in 500-ml bottle