Thanks, GoVols and Janci. I really like how clean your tank looks in this thread, definitely a different look than mine, which has coralline over most of the back wall and now forming on the areas of exposed bottom glass. But I guess I have to be realistic about my inherent laziness. Thank goodness for the Flipper. That little gem is the only reason I don't have any coralline on the front and side glass anymore. I can't use it on the back glass as my tank is up against a wall. I know very little about urchins but I worry about how they supposedly knock stuff around. I have quite a few new acro frags in my tank right now and I worry they would suffer from the urchin's bulldozer effect. Once the frags encrust I imagine the urchin's impact would be less. But, as I said, I know next to nothing about urchins and I may be worrying needlessly. I'll see what I can find out about them. (I know they would be a hit with my kids since they look just like Ghibli's Soot Sprites).
Thanks, again,
Kurt