I had a crocea clam for about 2 months. The first month he did OK, then shriveled up, you guys gave me good advice, and said to feed him phytoplankton. The clam did fine until yesterday,(wednesday) I came home from work and its shell was open but the clam itself was really small. I changed the carbon in the tank on Sunday and thought that was the problem so I took the carbon out wednesday night, and today the clam is dead. It appears 3/4 of its body is gone but what is left still has bright colors. He does not move when I pick him up, any ideas? Everything else looks fine or even better .