Lugol's solution, concentrated Iodine, 1 oz., Kent Marine. KENT MARINE LUGOL�S SOLUTION provides a key nutrient for marine invertebrates and fishes while promoting coral polyp expansion. Improves colorations and prevents bleaching of corals. Can be used as a dip for stony and soft or leather corals. Lugol's Solution is a strong iodine that is designed as a coral dip to eliminate disease causing bacteria but can also be carefully added to the display aquarium. Directions: Lugol's Solution is VERY strong, and must not be overdosed! Add 1 drop per 25 gallons aquarium capacity weekly to sump or an area of high water flow. Can also be diluted in one cup of aquarium water and administered directly over xenia colonies or soft corals with rigid tubing or a pipette. Do not mix with other supplements outside the aquarium. To use as a dip for corals, in a separate bucket add 40 drops Lugol's Solution to 1 gallon aquarium water, and immerse coral for 10-15 minutes.