We have just returned from 5 weeks in Belize and found no snorkeling from the beachs in San Pedro. If you are willing to stay at South Water Caye, there is truely awesome sites there. In one morning, right off the beach we saw the following; spotteed eagke ray, yellow sting ray, southern stringray, three green morays, trunkfish, hogfishes, all of the parrotfishes, trumpetfish, and a pair of sand divers, crabs and lobster just to name a very few!! This is the spot we will return to if we ever get a chance. There are two places to stay. We would recommend the Pelican Resort on South Water Caye, although there is no hot water.
email if you have further questions, email@example.com