I have a plate that has done very well for the past six months. I feed it weekly. I feed it at night to be sure the fish dont take the food and watch to be sure the shrimp don't take it. Any how, in the past week I have noticed a bit of skeleton around the mouth of the coral, about a 1/4 inch. What can i do..All of the other corals are doing great..Parameters seem to be in check, 0 ammonia 0 nitrites 5ppm Nitrates ph 8.4 SG 1.026 Temp 79 Lighting 8x54 T'5s The coral is on the sandbed of our 72 bowed... Any thoughts???