I have had this clam for about 15 months and all has been going so well. He was high on the live rock for many months and then started to jump so he has been placed in the sand for about 5 months. Yesterday I noticed my starfish was all over him and he looked unwell so i have lifted him back up high again but he jumped again overnight. I thought he was dead this morning but he reacted when i lifted him out of the water so i am leaving him in the tank. His mantle is really retracted and lost color and seems to be fleshy inside. Any ideas. Water quality is fantastic, lighting is good, no issues with anything else in tank!