My 1st Saltwater tank

After that hitchhiker thing sat there for a couple of days without moving, i decided to touch it with something to see if it would move. It was just a shell, so I figured whatever it was had died in the tank. Not so! Tonight while sitting watching my tank, I saw something come from under a rock cave and nearly scrared me to death. All of a sudden I see these hudge claws, then the rest of this thing comes from under the rock striaigt for the seaweed salad that I had just put in the tank. I jumped and he scooted back under the rock. I sat there for about an hour waiting for him to come back out so I could take a picture, but nothing. It looked like a large bleached out emerald crab. It definately had some big a** claws.
 
wow cool.... being greenish, it might be just a 'red emerald' crab which is alright but might pick at corals eventually and it gets big compared to the green mithrax which stays about 1.5 inches. I'd keep it and wait and see. I bet he's bleached out from fear or hunger.
 
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