Coral Color D:

A complex of 18 trace elements. These 18 elements (out of all the trace elements in NSW) participate in the metabolic processes inside a coral’s skeleton and soft tissue. D elements are related to the blue/purple chromo-proteins.
Red Sea’s research has identified 31 minor and trace elements that, in addition to the foundation elements, are present in coral’s skeleton and soft tissue. The Coral Colors supplement family divides these elements into four groups (Coral Colors A, B, C & D), with that are related by the biological functions they perform and are also associated with the production of specific color pigments in the soft tissue of stony corals. These pigments can be produced only if the specific elements required for the bio-chemical process are available in the correct concentration. All stony corals require all of these 31 elements, irrespective of the actual color the coral displays