GSP bad for Millipora?

[intarsiabox]

I'll have to try and move it elsewhere in the tank. The GSP came on a small frag of zoanthids I bought awhile back and it is growing very quickly. I never really planned on keeping SPS in this tank as I was waiting until I got my larger tank set up but I got a couple of good deals so I thought I'd try a couple frags out. They are both growing well and since my GSP has never bothered any of my zoas or soft corals that are in it's reach I never figured it for a stinger of SPS. I guess no soft corals at all in an SPS tank would be the safest way to go?