Salifert All In One Organic Calcium is similar to Coral Grower but contains an organic calcium compound rather than Coral Calcium. This organic calcium compound is broken down very quickly and does not contain substances such as gluconates, sugars or EDTA which build up and pollute the aquarium. This organic calcium is also rapidly transferred by bacteria into calcium bicarbonate, to be used by corals and coralline algae for their growth. Helps maintain levels of alkalinity and carbonate hardness.