"When I bought my first bottle of anti-fog in the store, I figured all anti-fogs were the same: they still fog up after a while. I was wrong -- ANTI-FOG SOLUTIONS ARE TOTALLY NOT ALL THE SAME!
I had to write this Aqua Sphere Anti-Fog review because it actually works. The solution goes on a lot thicker than the other one I tried. If you smear it around the surface of your goggles with your finger you'll leave finger smudge marks. But just trust it - if you follow the directions Aqua Sphere says to let it kind of set and then rinse with water. When the water hits the surface of this layer of anti-fog, it smooths it so it's not all smudgy anymore. It makes such a huge difference in open water swimming, where you need maximum visibility. I don't ever remember it getting foggy during my 1-mile swims. I couldn't say that with my other anti-fog solution.
Cons: none. Thanks Aqua Sphere!"