I am not aware of any diving close in to Placencia. You gotta go about 25 miles out, as far as I know. To get to reef or anything special. You'll see some stuff (the occasional barracuda or turtle) right off shore, but nothing too great; mostly sea grass. The folks who would really know is the dive shop at Roberts' Grove. They dive a lot; that's their biz. Or call/e-mail any of the dive shops in Placencia. MOst folks got to Laughing Bird Caye from Placencia, or stay at the overnight places like Serenade, Ranguana Caye or closer off Dangriga, Tobacco Caye.