It looks to me like the first crab pictured here-
Crab Hitch Hikers
If you are close to me, I'll toss him in my sump
It just showed up?
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No it must have been hiding this whole time. Just noticed him one night when all the lights were off. Sneaky bastard
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No I mean you didn't put it in so how did it get in. Sorry don't know much about saltwater saw this and thought it was kewl
Sent from inside my fish tank