Crab on SPS?

[DraggingTail]

Is a crab on my SPS beneficial?

 

[ca1ore]

Is the picture supposed to show the crab? If so, I don’t see it. If it was a wild colony, many of them come with commensal crabs. They are cool and do no damage.

 

[saltyhog]

Looks like a hermit on top of a bonsai? If so, the only time I see hermits on my SPS is if there is a dead area with some algae on it. I've banned all my hermits to the sump because of this behavior.

 

[Reefpuck]

Got a better pic?

 

[DraggingTail]

Yes, a red leg hermit is
climbing on it. You can see 2 of the on the lower right.

Do you see any tissue necrosis?