I have two emerald crabs and one disappeared a few weeks ago. Today I saw what seemed like its exoskeleton, bleached, in the sand. I thought, ok, poor bugger must have died for whatever reason. While contemplating its demise I noticed that the claws were indeed moving, and not because of water flow, it was feeding off some hair algae! I removed it gently and found that all its legs and one eye were missing. I know crabs can regrow limbs, not sure about eyes though. Since he/she seem to have survived an apocalyptic experience I thought it prudent to put it in the sump where it should have time to heal, if possible. Have anyone here seen crabs recover from such hectic injuries?