I posted several weeks ago. I have had a Gigas (believe that is its name) clam for a few months. I had it on a rock and seemed fine for quite some time. Several weeks ago he stopped extending his mantle (especially on the lower halves) and they are somewhat pulled in exposing the shell at all times. I tried moving him into the sand with no changes now. He is not dead but seems like hes heading that way. I do use DT every other day. Its a 135 tank. My Maxxima is doing well. All parameters are fine and nothing is touching him and I see no bugs. Any ideas?