I don't have a specific beach, but thus far, I found the Emerald Coast--in particular Destin to be gorgeous. The water is a perfect shade of green, at least on our visit. (until it is packed with tourists that is).
I live in Brevard and our water isn't clear at all--a bit dingy from all the sand getting stirred up with the tides. I wouldn't call it "pretty". But it's nice.