How to clean cloudy glass

You have to soak your cups for five minutes in white vinegar. Since it’s acetic, it’ll dissolve the minerals. If stubborn spots still persist, gently rub them off with baking soda. Then rinse the glasses by hand and dry them with a lint-free towel or a microfiber cloth.
To prevent future buildup you have to remove glasses from washing machine immediately after the wash cycle to avoid the high heat of drying, which can accelerate the etching