Posted this on Scubaboard and was told perhaps someone here would know what this is.
Fish was about 18 inches long. We found him on our night dive. After I shot 2 pictures of him (with flash of course) he headed straight for me and continued to be aggressive toward me for about a minute, til I was finally able to "push" him away with my fin. The rest of the dive he was continually in sight of one of the 5 of us (could usually see him in someone's light). The action reminded me of a trigger fish but I'm sure he is not a trigger. In my 250 dives I have never seen this color variation - though I thought that perhaps being at night might be a reason for the odd colors. We were in about 40 feet of water on a reef.
Curious to see what your opinions are.