Hard water stains; a major eyesore on glass.They can also be a pain in the butt to remove sometimes. For mild cases I recommend using simply vinegar,pure lemon juice and baking soda.

1. Spray lemon juice directly onto stains and let set for couple minutes
2. Mix vinegar and lemon juice in equal parts then add the baking soda to your solution until you get a consistency similar to that of soft scrub.
3.Using a scouring pad apply your mixture to the surface with small circular motions.For the corners you could use a toothbrush
4.When done rinse

Prevent new stains by spraying a solution of vinegar and water onto your shower doors frequently.

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