To remove water spots use this (I have used it commercially for many years on hundreds of thousands of dollars worth of glass with zero issues)
or (I have never used this product)
When your done cleaning the water spots use a sealer or you WILL get stains again!
This sealer can last years http://www.crlaurence.com/crlapps/sh...3&ModelID=4384
Never do the following to glass:
1) Wax your windshield. Wax is not for glass and will fill the voids, chips, and clevises and haze over time. It's for paint NOT glass.
2) Use steel wool of any kind. It creates hundreds of thousands of miniscule scratches that will make staining worse in the long run. They are not viable to the eye. Steel should never touch glass regardless of how hard you think glass and steel are. http://www.tacomaworld.com/forum/det...ml#post2034997
If you don't want to believe me or my almost 2 decades working with glass see here (from Oldcastle Glass the largest fabricator of glass in North America written in conjunction with G.A.N.A. Glass Association of North America) http://www.winecellarinnovations.com/glasscleaning.pdf
When cleaning acid etched, sand blasted, or frosted glass Mr Clean Magic Eraser is great. Sparkle listed above is also good. When your done cleaning it use a sealer so it stops absorbing oils, dirt, and chemicals.