I have just booked our return trip to San Pedro for August!!!!!! Oh happy happy day!! During our March trip we snorkled Hol Chan/Shark Ray Alley, Tres Cocos/Mexico Rocks and some great place with lots of sharks and Manta Rays by Caye Caulker. My question is this. Where else should we snorkel (and why) and who should we book with? Thanks in advance for any suggestions!!! August can't get here soon enough!