Thanks dick headers.
This clam is sitting on a shelf and he usually has a few hermits running around him, but I will also try to target feed him some phyto feast. I think it may have been the temp change in my tank. It was running at 78-82 and he was fine. I've dropped the temp to 75-78 to control my green algae problem, but he seems like the only one that's been affected. I'll keep you updated and once I get rid of this shitty algae problem I'll post some pics.