Can you tell me more about the UV light diving? A cursory search doesn't seem to show up anything about the dive mask filter you mentioned. From what I found, it looks like the lights are similar to regular low-power UV-A black lights that are not a hazard to skin or eyes.

What was the model of dive light used? Was is a long-wave light like those in tanning beds or disinfecting lamps? I would imagine that any light unsafe for your eyes would also be damaging to the coral and fish.