Originally Posted by Keithhjs
Emerald crabs are great for clean up crew but care should be taken with Sally lightfoot crabs as I think those aren't really "reef safe" crabs.
I've had two, one in two different 30 gallon reefs, and I never had any trouble from them. I have heard of other people having nasty ones, though. I do agree, there are better options than Sally's. Regular old Mexican red legged hermits and scarlet reef hermits are excellent. You'd be hard pressed to find many full sized reefs without them anywhere in the world.