I leave mine, I don't have any purple, but the light, and dark green.
I also have a Rainbow Poci- I havedn't heard anyone mention.
It seems to be a slow grower, and hasn't shed/dropped any polyps- yet.
It's a really cool looking one as well, sorry- at work and can't upload a pic.
I do have smaller green ones in several area now.
I had a huge solftball sized drop all polyps w/in 1-2 weeks, and I pulled the skeleton.
Params and all other coral were fine at the time.