Alexander Springs, located in central Florida, is known for its safe open water dive.  The shallow depths and small caverns make an for excellent novice dive.  The spring basin is one of the largest I’ve seen, almost 300 ft. wide.  While depths don’t exceed 27 ft, there is a very small cavern to explore that make it an enjoyable scuba dive.  Snorkelers can also enjoy the basin and freedive to most of the exciting parts. The main cavern can be penetrated for about 10 ft. at a depth of 23 feet.  There is a strong flow at the deepest part from a vent.  There is a lot of marine wildlife here and a chance you might even see a gator!

http://www.lakecountyfl.gov/hometown_highlights/alexander_springs.aspx