Three component Iodine for healthy corals growth and bright colors. This is an iodide additive especially developed for salt water aquaria, supplying iodide as well as organic and elementary iodine. Whereas iodide and elementary iodine are immediately available for animals and plants, the organic bond releases iodine slowly and ensures a long term supply. Iodine is an essential trace element for all invertebrates and especially for custacea which require iodide to assist in sloghing off their shells. When provided with iodine, corals show faster growth and more intense colors. 250ml bottle.