Is the clam fully extended and look healthy from above??? Or only partially??? I lost one of the crocea's I got from Prem Aquatics about a month ago, but it never looked too healthy... I just really liked the coloring, so took the chance... That looks like an Astrea shell to me too... But its crazy how deeply embedded it is into the clam... Or maybe thats just the pic... But reguadless, one of my clam's foot is attatched to an old Margarita shell, but you can see the "threads" of the foot, and it hangs down a good 1/2" or so... I know that the snail preds of clams are a lot smaller than that... Think of a grain or rice... They come out at night though, and you scrub them off with a toothbrush... Least that's what I've read... You don't have any fish in there that could be picking at it??? I had a lemonpeel that loved my blue maxima... Little *****... They had to be separated... I don't think you "dip" clams though... How deep is your sandbed??? Hopefully someone in the clam forum can help more...