Lugol's is the strongest source of free iodine and iodide available on the market today. Due to its high concentration, Lugol's provides an excellent source of iodine for all corals, marine fish and other reef invertebrates. Using Lugol's as a supplement will increase the vitality and polyp extension of corals. In addition, Lugol's will help corals maintain their natural color and will help protect them against bleaching. Using Lugol's as a dip is a very effective treatment for new corals being added to the aquarium, as well as for treating damaged coral specimens.