I have been scrubbing my shower door's hard water stains with no results. The web said to try Lemon Pledge or Bar Keeper's Friend. I tried the Pledge first and it didn't seem to work, so I tried the Barkeeper's friend on the same spot and a little more. The area where I used both is now spotless. Yay! Pledge first, scrub, wipe off. Bar Keepers friend on a moist scrubber, scrub, rinse. Easy!