BlueSpot;875025 wrote: I have usually have great luck with emerald crabs, even other mithrax besides the greens. I recently got a few more for the tank. One was a big one and it proceeded to ignore the algae and start eating several snails and hermits a day. I easily got him out with a net. Wasnt afraid of anything. His hole had about 10 shells in it. The smaller ones eat a ton of BA. That was one problem crab out of about 40 I have bought in the past. I will always try to get smaller ones from now on though.