I recently ordered a copy of Alex Mustard and Peter Rowlands Shooting Magic DVD. I have been using magic filters (
http://www.magic-filters.com/)in blue and green water for some time. This is an example of a green water shot:
What is amazing is that the combination of filter and high ISO/slow shutter has meant that it actually shows more detail than I could actually see through the viewfinder! I've had a similar experience using a green water filter on my video camera. The blue water filter brings out the fantastic coulours on the reef. This was shot using a blue water magic in the Red Sea:
Anyway, the DVD arrived and it is amazing how much more it gives! The practical advice on all sorts of things-even just getting the Anthias to point in the right direction(!) is great. You can order it from magic filters at
http://www.magic-filters.com/