Hi - if you mean Lugol's Iodine dip - I use it to dip my corals in before adding them to my tank. The directions say 40 drops in a gallon of the tank water. I take a large gallon container and drop in 40 drops (or a 1/2 gallon takes 20 drops) and set the coral in the solution for 10 minutes. Then remove the coral - dip in regular tank water (with no iodine) to rinse it and then add to the tank. DO NOT use Lugols on any inverts or clams. If you have any questions about what corals are safe to dip in Lugols, check the internet. Hope that helps...