Sometimes my tuxedo moves over some of my zoo's...Can they eat thru the outer skin (not sure what the technical term is) if they're closed up?

anyone??

I don't know about Tuxedo's, but I had a longspined urchin in my 95 gallon and I had to get rid of him. He killed xenia's, a maxima clam, and at least 50 zoas. They usually don't eat corals, but if they get hungry enough it's protein:) Personally, I'm not going to have urchins in my reef tanks anymore.

That, my friend, is quite the sig.

Yes I know, maybe a little too extensive...haha...Yea I doesn't seem like he's eaten any of them yet, but he rolls over them sometimes and I always get paranoid he's going to munch into them...There is plenty of coralline for him to eat in my tank, and I've never fed him, so I would imagine he never gets hungry to the point where he'd eat any of my zoa's.

As long as there's enough food for him to eat. The longspines get rather large and when he ate all of my algae is when he started eating corals. I would throw in clumps of chaeto, ulva, and red grac macro to feed him, but it wasn't enough. He'd devour it.. Anyways, they're really cool animals. You'll notice if it starts eating your zoas. They'll have chunks of tissue missing from them or it'll sit on the same spot for several minutes and leave a empty spot. I believe soft coral eating urchins are pretty rare though. Didn't mean to scare you...