No bueno Looks like Gorilla Crabs IMO. I'm sure I'm gonna be scolded for saying this... but I'll say it anyways A lot of my friends are vendors and I help them when they get in shipments. When we dip and find Gorilla Crabs they always say to toss/flush them. However, I can not look in those blue eye's the crabs have and kill 'em I've put a few in my refugium and have not had a case of cyano since. I have battled w/ cyano in my fuge quite a bit but not since adding them. Now saying that, I'm fully aware of the risks of them houdining their way into my DT and causing chaos but I'm willing to risk it in the name of research
DISCLAIMER: IN NO WAY AM I RECOMMENDING ANYONE DO WHAT I HAVE.