New Coral Hitchhiker.. Help?

I bought this rock from a lfs with xenia, and it has this as a hitch hiker, as well as two polyps of some sort of zoa. All for 6 dollars



This is what I just glued to a rock, its got little polyps like a xenia on it, with green tips. Very very small. And the "stem" is purple. I tried to get a good picture...


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I think there may be a picture missing?

 

I decided the other two were to fuzzy. But that is what im trying to ID.

 

Are you sure thats not the stolon of Green star polyps?

 

That's what I thought by the way he described it.

 

They are green star polyps. It opened up while I was gone running errands. They are incredible.


Can somebody explian to me where it would be best for me to place these in my tank?