Yellow wrasse vanished


I have a 46g bowfront tank with 35lbs live rock. One of the fish is a yellow wrasse and i had it for about 2 months. The last 2 days i can't find it. it seemed healthy and liked swimming in between the rocks. I think maybe it moved to much sand around and the rock shifed and pinned it. or, and i hope this is not true, my halloween hermit crab ate it while it was sleeping in the sand
. the hermit is about half the size of a golf ball, at least the shell is that big,a dn i was worried it might attack a seahorse that i have. Should i get rid of the crab or is it not likely to attack fish.