float with the life jacket on rather than worry about swimming.
Where we went, the water went from deep (18 feet or so of crystal clear water) with thousands and thousands of very small fish (all the same kind, about 2 inches long) all around us that would part like the red sea as we swam through them, to shallow water with bigger and more varied fish swimming by.
That day, and at that location, the water was the calmest, clearest water full of sea life that I have ever experienced.