I dose approximately 2 cc of iodine into my 55 gal reef twice a week. The mushrooms and other soft corals are doing great. Due to lighting inefficiency, I don't keep any hard corals. Is the iodine really necessary? I also dose kalk (1/2 gallon - twice weekly) and I use the SeaChem Big Three (Reef Plus, Complete, and Calcium) 2 cc twice weekly. I was just wondering if the extra iodine is needed or not....