I found this guy while cleaning the reef tank at the petstore I work at. He was in our 200g display tank and I only found him because I was moving around live rock and he didnt hide fast enough. Its dark purple under the halides and appears almost black in normal light. It curled up in a little ball when I took it out of the tank. Its fairly small in size, could probably sit on a quarter and not cover the whole thing. It has probably been there quite a while as we havent added new rock or anything in over 6 months, and I havent seen any evidence of it eating corals or fish (but in that large a tank you never know). Id like to know if we can put him back or if we need to find him another home. I took some photos to help ID. Please let me know if he is safe or not, if he is I may put him in my tank at home. Thanks!

(I have more pictures if there is something specific that might help identify it.)


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Advanced Reefer
I will be honest I have no idea what species that is, but I would not suggest putting it back into your display tank. Most crabs are not very good other than a few species.


Sea Turtle

Advanced Reefer
Cool looking crab. Honestly, he looks like he could cause some damage to your tank. I had one in my tank that was a littel smaller. I got rid of him because I think he was eating sps'.


Coincidentally been reading the Calfo/Fenner book on reef invertebrates, which at some point says that trying to find good rules of thumb for deciding whether crabs are reef safe or not is difficult. However, it does suggest one - big claws, made for crushing, probably mean the crab is going to cause a few problems. I think yours might be one of those.

Good book, btw.

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