What do emerald crabs eat in the context of a display tank? On a very related note, I have a few, nickel sized patches of green hair algae that's maybe 1/4" long (at the moment). I want something that will go after this. Of my current CuC (which is diverse and huge), only the Chitons seem to eat it, but they are very slow. Very. I'd rather an invert take care of this over a Blenny or anything. If possible. What doesn't eat it: blue hermits, ceriths, nerites, limpets, planaxis, peppermint or skunk shrimp, clownfish . Params are excellent. Nitrate finally 0'd two weeks ago and has held. Phosphates have dropped and are almost 0 according to API test kit. I'm thinking an emerald will zero in on these patches. Thoughts?