Hairy Crab in our New Tank

[NewSalty]

Hi all,

New to this. We have had our live rock in our tank for about a week and have noticed just today that we have a hitchhiker (brown hairy crab). After reading many sites and blogs we decided to take rock out and flush out the little guy with cold freshwater and out he came. Is this a bad crab to have. We aren't sure what to do with him now. If he is bad how do you dispose of him. We have to go back to the store to get some things so do we take him in with us and give it to them to confirm he is indeed a bad one to have in tank?

Any help/ideas is greatly appreciated.

We also have another crab in our tank but notice that he is more like a big hermit crab (minus the shell). I will attach pic of him if I can get a good one on here.

Ugh - I can't get my pictures to compress to a smaller size (suggestions??).