Blue Grotto is a privately owned dive resort and freshwater spring located near Williston, Florida. It is one of the most popular diving destinations in Florida and is known for its crystal-clear water, abundant marine life, and variety of diving activities. The spring is fed by an underground aquifer and has a constant water temperature of 72 degrees Fahrenheit. Blue Grotto is home to a variety of marine life, including fish, turtles, manatees, and alligators. Some of the most common fish seen at the Grotto include sunfish, bass, catfish, and crappie. Turtles are also frequently seen in the spring, and manatees are occasional visitors. Alligators can be seen in the spring run, which is the channel that flows from the spring to the nearby Suwannee River.