Pink Sea Urchin or Emerald Crab?

[Groot]

Was trying to get rid of Caulerpa Alga along with some bubble alga. Picked up a tiny Emerald and small Pink Urchin couple days ago. I had bought a single polyp of LSOH back in January and was up to 5 heads. Now I'm back to one head. Not sure who the culprit is. I was lucky enough to grab the Emerald yesterday and I have her separated but I'm not sure who it could be. I hope its not the Pink Sure Urchin, I like her but I'm not convince she is innocent.

 

[Joker]

I would lean more towards the emerald crab than the urchin. But I have had urchins start to eat coral out of random as well. I had a long spine start to eat my monti caps.

 

[Groot]

Interesting. I don’t think I head that, zoas yes but Montipora no. I have some Montipora and Digi we will have to see.

 

[Mimiminite]

My pincushion urchin will frag or unglue corals for me and drop them elsewhere. She's currently roaming about with some (happy looking) pipeorgan as a hat. Might be worth looking in cracks for the missing heads.

 

[Groot]

I was not convince yet that the sea urchin is innocent but I'm leaning towards the crab and I don't even know if its a emerald crab. I have the crab in container a.t.t. with nothing to eat except a small chunk of bubble algae and some caulerpa. She has not touch it at all. I should take picture of her.

 

[skippylou]

I've definitely had small zoa polyps eaten by an emerald crab before (but their utility far outweighed this collateral damage haha), but oddly that's the only coral I've ever seen them eat myself.

 

[Groot]

This one is not even eating algae.

 

[rock-n-reef]

make sure they are not gorilla crabs instead of emerald.