Hermit Crabs

[jburgi]

I have a random hermit question. I got 3 scarlet hermits about a month or so ago. They are really cool, but they have really long shells, which they seem to have a rough time navigating.
Anyway, I have been meaning to get some other shells for them in case they wanted a new mobile home, but I haven't got around to ordering any yet (I don't really have a lfs where I live). So today when I was cleaning my tank I noticed that one of the hermit shells was empty. I was sad because I thought that he must have died. Then after I was done cleaning and admiring my tank I found him! He killed one of my snails and stole its shell. The killing of the snail for the shell is not what I found peculiar...what I found so strange about it was that the shell that he moved into is more than half the size of the last shell! I thought they moved up, not down! Especially since if he was going to steal a shell from a snail there are bigger snails in the tank!
So I guess I am curious...is this normal? When I get more shells for the hermits, should i get some that are smaller as well as larger?

Thanks for reading my rambles