[newfoundlove]

hi everyone,
i just got my first hermit crab about 4 days ago (killer is his name) and he's been doing great, i read on the internet to get him company, so today i went to the pet store and got another one, same size and all. Brought him home, put him in the tank with killer, go for dinner, come back and he is gone. Ive looked all over the tank for any signs that he mite have dug under. is he molting already? or is it possible that the other one at him and hid the shell? shud i ry and find him? today i come home from work, and now killer is gone as well. i have an empty tank, lol. and i am worried about my little ones. any advice? thank you !