Zoas eaten by Urchin?

[charlypooh]

I've got two pencil urchins in my tank and one of them made it to the front of the rock pile a couple of days ago. I had a small 3-4 polyp frag of Blue Tubbs, and a single polyp Happy People Eater frag plus several others in the area where the urchin ended up. Now, I have no Blue Tubbs, and my HPE is missing 3/4 of its head. Has anyone ever had a problem with a pencil doing this before? I've had two in the tank for 3 years now and have never had them munch on anything they shouldn't...

 

[charlypooh]

I come home today to find the urchin made it to the front of the tank again...another new frag of 3-4 polyps gone, and he ate most of my gorgeous pipe organ frag. Time for urchins to go bye bye.