I'm not sure as I keep very few corals in my tank. I have noticed that most coral tanks do best when there are fish in the tank and suspect the detritus and fish food are appreciated by the corals. Before you try supplements, you might try grinding up and feeding a tiny amount of finely ground regular table shrimp and moving the mushroom or lighting to where it gets more light. I do add a tiny amount of vitamin B and iodine no more than once a month but sometimes I think even that has a slight negative impact.