Porcelain crabs DO harm Bubble Tip Anemones!

[Ozzi-reef]

I did a lot of research before getting Porcelain crab to host in my Nem tank and everything indicated they were safe with Nems. So I got one and she was originally in with a large GBTA but that Nem caused so many issues in its constant wandering I ended up taking it back to the LFS. So that left the crab with 4 small BTA's in the tank - one pink-tip, one Candy Apple and two Forest Fires - All around tennis ball size when fully inflated. I noticed that the Candy packed up and was gone and found it hiding in the most difficult to reach place behind the outflow. The two FF periodically disappear into crevices. Then today I found the crab sitting on a totally deflated pink-tip nipping at its tentacles. I first wrote this off as 'cleaning mucus' which they are known to do, but then I saw the evidence of darker activity - a small bit of tentacle ripped off. Any advice on why the crab is doing this and what to do (I guess removal of the crab is the only option). Excuse the blurry photo of the separated tentacle - best I could do with angle and iphone.

 

[AviR]

So sorry man

 

[SauceyReef]

Hello!
Curious what ended up happening here??