[mike31154]

Mine is not green either & think it's still considered an emerald crab. Not out much under the lights, except when feeding time. They can sense/smell when food hits the water, especially raw fleshy food like silversides or chunks of shrimp. Like I mentioned in my earlier post, an emerald would try to steal food from my BTA. Even my cleaner shrimp would grab stuff from out of it's tentacles. Now that the BTA is sticky & healthy, neither shrimp nor crab goes near it even when feeding silversides.

When I had two, each one seemed to hang out in opposite rock piles, territorial just like the fishes. They must have fought occasionally since both emeralds were missing appendages at various times. I'd definitely say more active at night. Get out your red light & you'll more than likely see it roaming around in the dark. Also depends on what other livestock you have in there & how long your system has been running. I see the crab out more often under the lights now that the tank's been up for years. Certain fishes don't take kindly to crabs & will take runs at them, depending on size & species. Survival instinct is strong.