Great pics. The Virgin Islands were the first place in the Caribbean I ever went about 20 years ago. I especially like the first with the sting ray and remora, the one with all the juv. grunts with the fan worms in the background, and the last one with the bait fish that really shows what the underwater scenery looked like. It appears you were fortunate to have very clear water for your pics.
I am an avid snorkeler-photographer (don't scuba dive), so I am always interested in seeing good snorkeling shots. I've always wondered how much harder it is to take pictures snorkeling vs. diving. I queried about this once on this board and didn't get much in the way of response. I don't think most divers are very interested in snorkeling.
About 6 months ago I bought a Canon A630, which I presume is similar to what you are using, but with more mpx. I've only used it on a couple of trips to Destin in the Florida Panhandle, where the water is somewhat greenish-murky, so I haven't given it the full test in very clear tropical waters. My pictures are here:
Destin Florida Underwater 2007 Photo Gallery by Dave_Clausen at pbase.com
With just a few exceptions, most of the photos were taken with available light. For these pictures, I set the mode (dial at the top) to Av, and then set the ISO to 100 to make sure I didn't get noise in the photos. I let the camera do everything else auto. The camera usually set shutter speed to 1/500 and F-stop to 2.8-3.5. I was reasonably happy with how the photos turned out, but most seemed a little dark. I don't set white balance underwater, and adjust all the photos later in Jasc (now called Paint Shop) or Photo Elements to get good color. This usually seems to work o.k. I tried a few pictures in Canon's automatic underwater setting, and they didn't turn out well at all.
My previous camera was an old Canon S30 (3.2 mpx; all the uw shots other than the Destin 2007 album at my PBase photo site were shot with this). I just set it to auto for everything; unlike the newer Canons, the auto setting for this camera does not let the ISO go above 150. The uw pics did turn out surprisingly good, and were not dark like many of the Canon A630 seem to be. Therefore, the big advantage of the A630 compared to my old camera appears to be merely the increased number of mpx in the A630, which allows for much more cropping.
Since I really liked the color in your pics, could you tell me what settings you were using on your camera? Did you white balance underwater, or adjust the color later in a photo editing program? You weren't using the automatic underwater setting, were you? Your pics appear to have very little noise, so you must have been using a low ISO setting. Thanks for any response you can give.
Dave