HCA: Hermit Crab Association

I recently adopted 2 new crabbies to keep Sharky company after Pinky, his companion of nine years passed away. A couple of days after I removed Pinkie's body, Sharky buried himself and hasn't been up to eat or drink in about three weeks. I don't know if he's molting or lonely. If he's just lonely, I have 2 smaller playmates ready to keep him company.

One of the new guys already changed shells and I haven't seen him for a few days. The other one is coming up to eat and drink at night. My smaller tank isn't ideal and I really want to move them to the large tank. Should I wait for the buried new one to come back up and move them both at the same time or is it OK to move them separately? Is it OK to move the new ones over if Sharky isn't lonely, but actually molting, they are smaller than he is?

I would go ahead and move the new ones to the new tank. Then wait for Sharkey to come up, and give them all a quick dip in the fresh water in the new tank, so they all smell the same and nobody smells 'new' compared to the others.