I have had healthy greenstar polyps in my reef tank for a couple of years now and it grew quit a bit, but for the past few months I have noticed that it is getting smaller and thinner on the rock. Any ideas what could be the problem? I have been feeding it with Kent Marine Phytoplex and baby brine shrimp. I have been adding Strontium, Calcium, and Iodine as directed, and am not sure if I should be adding something else. I keep the Sp. gravity at 1.021, and the pH at around 8.2, and keep the temp. at around 84-85 degrees F. I have plenty of florescent light. It's seem healthy and happy, except for the slow decline.