Emerald crab grazing on SPS?

[P. mandevillei]

I’ve been spotting my emerald crab dwelling on SPS fragments and seemingly trying to snap the polyps. Though I didn’t see it actually eating the corals, it’s harassing them greatly. Is this a predatory behavior and is there a way to stop it? Will feeding the crab help? 

[EireSPS]

I’ve had this occur as well in a prior tank. Emerald just couldn’t seem to resist eating/destroying my mint pavona.

 

I tried extra feeding and it made zero difference, but what didn’t work for me, might work for you. It’s worth a shot if you’re set on keeping it in the tank.

there are a multitude of threads on other forums about people having similar issues (eating sps). Some seem to be able to temper it with food, others not. 

 

ultimately, the crab had to go bye bye.. and I no longer have any crabs in my tanks. My SPS are too valuable. 
 

 

[P. mandevillei]

Thanks! That is too bad… I guess I’ll have to move it out to my another smaller tank with only soft corals.