Carbonate & buffer complex for balanced formation of Coral Skeleton KH 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. Red Sea’s KH/ALKALINITY is a complex of carbonate and other buffers present in seawater that maintain proper alkalinity and pH, and is part of Red Sea’s complete Reef Care program. Aquarium Type Average daily usage Liquid ml/100L (25gal) Powder g/100L (25gal) Mixed Reef 9ml 2.7g SPS Frag 18ml 5.4g SPS Dominant 12ml 3.6g Ultra Low nutrient SPS 6ml 1.8g Concentration: Liquid supplement: 1ml will raise the Alk level of 100 liters (25 gal) by 0.036 meq/l (0.1dKH) Powder supplement: 1g will raise the Alk level of 100 liters (25 gal) 0.12 meq/l (0.33dKH) 1 kg will make 10L of stock solution. package size/volume : 500 ml (16.9 fl. Oz.)