There are several things you can do to get rid of hard water stains in a toilet. Many commercially-available products claim to remove these stains, but most require more than one application. There are also home remedies that can prove to be successful, such as applying cola soft drinks to the stains, using a pumice stone to rub away the stain, and even using fizzing, antacid tablets. You might also wish to make a paste of baking soda and water to remove hard water stains.
Hard water stains are caused by high levels of calcium and magnesium in the water supply. This can result in brown to copper-colored staining in toilet fixtures, sinks, and bathtubs. Commercial cleaners typically require users to apply the product and allow it to sit for a specific period of time before scrubbing. These often work best if you remove the extra water from the toilet bowl prior to applying the cleaner.
Stubborn hard water stains in a toilet can require scrubbing with a soft-scrub pad to remove the stain. If using the pad in conjunction with a chemical cleaner, you must be sure to wear protective rubber gloves. The strong chemicals used in these cleaners can harm or irritate your skin if allowed to come into contact with your hands. Some remedies, such as using cola-type soft drinks, are less irritating on your skin, but they may require numerous applications and extended scrubbing to completely remove the stain. For light stains, placing a denture cleaning tablet and allowing it to fizz in the bowl will sometimes be effective.
Antacid tablets, such as those that fizz as they dissolve in water, are also a good choice when attempting to remove hard water stains in a toilet. You may have success in removing the stains by dropping several of these fizzing tablets into a clean bowl of toilet water and then scrubbing the bowl with a toilet brush after the tablets have stopped fizzing. Another home remedy calls for the use of a pumice stone, such as those used to remove callouses on feet, to scrub the stains away. This method, although successful, may scratch the inside of the toilet unless care is taken to keep the area wet while scrubbing.