Here's one point where I differ from Lando. Anything with claws has been removed from the tank. The hermits that survived were relegated to the sump. Hermits will kill each other and snails for their shells and I prefer the job the variety snails I have do to having hermit crabs munch on them.
I tried having plenty of empty shells around but the blue leg and scarlet fought each other and snails over and over. Overfeeding the tank did not help.
I suspect Lando is spot feeding his hermits with valium