I have two urchins in my tank, one blue tuxedo and one pin cushion. They are the best part of my CUC and are doing a great job of demolishing my hair algae, but my pin cushion keep picking up cerith snails and holding them upside down on his back. The tuxedo just puts algae on his shell. It's still amusing, and there's no way I'd ever get rid of him. My fiancee is attached as well. What does your urchin carry around the tank?
And stays a nice small size.
