Crab ID-Not sure what it is

[racinrob3]

I have a 55 gallon tank which was running over a year before I saw this guy. I started the tank myself which is why I was so confused on where he came from. I think part of the reason he was never seen is my Huma Huma was not real crab friendly. Now he has a new home so my crabs and snails can live in peace. Thanks for your help.
Rob

 

[hunt]

That looks like a gorilla crab, How Big is it?. You should get it out, they will eat almost anything they can get there claws on, includuding fish.