should a clam just go into a slow decline, taking a few weeks to gradually die? lg maxima. mantle slowly receding more and more. he was fine for 2 weeks. the other 12 clams in my tank are fine, is it just failure to thrive? no nipping, no flow, lighting or water quality issues. certainly no pyr bstrds either. most other clams ive lose in previous situations went overnight. this poor guy is hanging on for his life. every day i expect him dead, but not yet. no radical treatments either, no fwd, which will def'ly kill him.