Tank, coral, fish and clam were all looking great before I went on vacation. When I got back a week later everyone survived and I did not observe any ill affects... save for the clam. It is shut tight. The only change I've made recently is dosing Red Sea trace elements A, B, C, & D and Reef Energy A&B in low doses. I performed a water change yesterday but the clam is still not opening up. Does any one have some suggestions?