crab ID?

[boshk]

any idea?

I know for sure its not the good one (Porcelian)

Found 2 on my curing live rocks. There's another red one hiding in the rock I can't get out.

Thanks

Also, if its bad, how do I flush out the others?
5-10mins dip live rock in high salinity water? 1.04/53ppt+??

 

[Ron Reefman]

I'm not a crab expert, but to me it looks like a Mithrax (Emerald Crab) only you have the Ruby version. We see lots of them in the Florida Keys. Reef safe.

 

[Dkuhlmann]

Can't really tell from the pictures. Mithrax crabs have little flat pads on the tips of their large claws. If it has those then it's a Mithrax.

IMO and IME there is no good crab with the exception of maybe the Porcelain crab and my favorite the scarlet hermits.

While Mithrax crabs are good at eating algae they will more than likely go rogue once mature which is about an inch between shell points. They can and will kill fish while the fish are sleeping and can and will eat corals.