I also read your report on Yal Ku. I was very surprised to read that you didn't see many fish. We were just there a few weeks ago and saw tons of fish, with lots of large schools. I did swim out toward the ocean one day and there weren't many fish in that area. But if you go the other direction, you're practically surrounded by them. My son took nearly all the pictures on his underwater camera in the first 60 minutes.
The only difference between this past trip and the trip we took in 2001 was that we didn't see a nurse shark this time and I didn't see any of the "angel" kind of fish, although my husband said he did.