How to Remove Hard Water Stains in a ToiletBy VIRIMI / March 31, 2021 The Spruce /Taylor Nebrija 2 . Add about 1 cup of baking soda to the toilet bowl, then add another 1 to 2 cups of vinegar. This will create a fizzing action. Let the solution sit for about 10 minutes. ADVERTISEMENT [DISPLAY_ULTIMATE_SOCIAL_ICONS] Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17