Lighting for my Tri-color Acro

[Genghis]

I just setup a 30 gallon SPS tank w/ 150w MH and 10 gallon refugium. I had my water tested at my LFS and was told that everything was in the right ranges. I've noticed a pattern with when my acro decides to extend its polyps and when it closes up. I was just wondering if the coral prefers lower levels of light or if it's still acclimating to that amount? When I have my canopy in it's closed position, the coral will refuse to open up. When I leave my canopy open ( top is straight up, not in the 45* position) the polyps will open up. This isn't something that happens instantaneosly, but probably after 30 minutes. The polyps will remain to stay open as long as I leave the canopy open, but will close up slowly after I place the canopy down.

I also have another acro frag that refuses to polyp at all, day or night. I went back to the LFS and checked another frag that came from the same colony and noticed it didn't open its polyps in the store. I'm not totally sure, but it looks like its losing some color.

Sorry for the extraordinary long post, but I just wanted to make sure everything is going well. Any help will be appreciated!