Tony the coral behind it to the right, out of focus, green too. I understood Ben to say it grew from a quarter size so it did not encrust but grew that skeleton.
Here's the rest that's half way decent. I'm still learning the best way to take pics of tanks so be kind...
Jess - sorry there aren't more of your setup but the reef brites really played havoc with my focus. I'll try again next time.
Chris - the 600g FOWLR setup only has a few pics. The dark blue from the depth of the tank was a bit of a challenge. All pics of it I had to manually lighten with my phototshop clone....afterwards there were only a few worth looking at...