I have never had a problem of any kind with this clam that I had.  I had him about 6 months or so and all of the sudden when I woke up this morning I looked in the tank and seen it wide open with a bunch or red legs just going to town on it.. Im just shocked.. I dont know what happened.. Never seen that happen before.

Hmm...about like my first clam experience. I think crabs like clam....perverts!!........OH @#$* .....no I do not have crabs personally....just our tank.