I go diving with Tulu (he works out of the Coral Beach Dive Shop)--he's very good and knows the dive sites well enough to show you where all the hiding things are. Overnight trip on the Offshore Express with Capt. Horace, Clive, et al is also out of the Coral Beach shop. They leave early am, 3 dives the 1st day, overnight at the booby bird sanctuary key (can't remember the name), so you can sleep on the beach or on the boat and then head to the Blue Hole for a dive and 1 more dive before you head back to SP.