Stubborn stains frequently develop in the toilet, leaving toilet bowl rings and hard water residue. These stains are dark, slimy, and make the toilet look like it has not been cleaned in ages. This makes it important to keep your toilet bowl clean, and removing these stains is a fairly easy procedure when you know which cleaning ingredients to use. More than likely, you have the necessary cleaning items already on hand.
Pour 250 ml (1 cup) of baking soda and 500 ml (2 cups) of white vinegar into the toilet bowl. Pour the vinegar around the lip of the bowl, and it will work its way down to the bottom of the toilet, softening all stains and residue. Let the vinegar and baking soda sit in the bowl for 30 minutes.
Scrub the toilet with your bowl brush, and notice the cleaners have loosened all the stain residue.
Flush your toilet and check for remaining residue. If any residue is left, repeat this procedure, but this time double the baking soda and vinegar measurements, and let them sit overnight before you scrub again with the brush.