Hard water stains on glass lead to unsightly white spots and a cloudy haze that can be hard to clean. These stains are caused by the residue left behind from contact with hard water, which is full of minerals like magnesium and calcium. If you know the right cleaners to use, you can remove these stains in no time.
Removing Hard Water Stains From Glass
The first step in cleaning hard water stains from glass is gathering the supplies you need:
- A bucket of warm water
- A cleaning solution
- A sponge with a glass-safe scrubbing side, a soft bristle brush or a "Magic Eraser"
- A squeegee or a lint-free towel, microfiber cloth or terry cloth
- Plastic gloves are recommended, especially if you are using an acidic commercial cleaner
To clean the stains, follow these steps, with some slight modifications depending on the cleaning solution you use:
- Apply the cleaning solution of your choice to the glass surface using either a spray bottle or a dampened sponge or cloth.
- Let the solution sit on the glass for up to five minutes.
- Take your sponge, brush, or Magic Eraser and work the solution into the glass to get at difficult stains.
- Take one of the clean cloths and dampen it in the bucket of warm water. Rub the damp cloth into the glass to remove the excess cleaning solution.
- Use either a squeegee or a towel or cloth to remove any excess water and solution that remains and dry the glass.
Cleaning Solutions for Hard Water Stains
You have a few options for cleaning solutions. These can be cleaners you buy or ones that you make at home using ingredients in your pantry.
Commercial Acidic Cleaners
You can buy a commercial cleaner that is acidic to clean hard water stains. You can tell if they are acidic if they contain any of these types of acid: hydrochloric, sulfuric, phosphoric, or oxalic. Examples are Bar Keepers Friend and Acid Bowl Cleaner. Note, if you use any of these products, it's important to wear gloves and eye protection and observe any other safety precaution instructions from the product labels. These chemicals can be harsh on your skin as well as your eyes and breathing if the area is not well ventilated. These cleaners should only be used on the surfaces indicated in the packaging as they can cause permanent damage to other common surfaces like marble, aluminum, enamel, and tile floors.
Vinegar is an excellent all-around household cleaner. Because vinegar is an acid, it can be very effective at breaking down and removing hard water stains.
- Mix distilled white vinegar with an equal amount of warm water in a spray bottle. You can mix it with cold water, but it will be more effective with warm water.
- Add in a drop or two of fresh or bottled lemon juice for a fresh citrus scent.
- Spray the mixture on the glass and let it sit for five to 15 minutes. For more difficult stains, you can let it sit up to 30 minutes.
- Take your sponge, brush, or Magic Eraser and clear away the excess vinegar and stains.
- Take a clean, damp sponge or cloth and rinse the glass and clear it of any remaining deposits from the vinegar.
- Use a soft, dry towel or cloth to dry the glass, or use a squeegee.
Salt and Baking Soda
This is an effective option for difficult stains and works well when combined with a water and vinegar solution.
- Stir together a 50/50 mix of regular table salt and baking soda. Add a few drops of water at a time to make a thick paste.
- After you have sprayed the glass with the water and vinegar solution and let it sit, take the salt and baking soda paste, and apply it with a brush or sponge onto the vinegar-coated glass.
- Using your brush, sponge, or Magic Eraser, work the paste into the stain until it is gone.
- Rinse the glass with a damp sponge or towel to remove the excess vinegar, salt, and baking soda.
- Dry the glass completely with a squeegee, towel, or cloth.
Ammonia can be work well on hard-to-remove mineral deposits on glass.
- Add 1 cup of ammonia to a bucket filled with one gallon of warm water. Add in 1/4 cup of baking soda.
- Dampen a brush, sponge, or Magic Eraser with mixture and rub it onto the stains on the glass.
- Rinse the glass with a damp sponge or towel to remove the excess solution.
- Dry the glass with your squeegee or cloth.
Mild dishwashing soap can work on hard water stains on all types of glass surfaces. Mix the soap in a bucket of warm water and use a sponge or brush to work it in. Rinse thoroughly with cold water and dry the area thoroughly.
Non-gel plain toothpaste can be used to remove stubborn hard water stains.
- Place some toothpaste on the stains and rub the paste into the stain with a damp sponge, towel, or magic eraser.
- Let it sit for five minutes.
- Take a clean damp sponge or towel and rinse the paste off. You can opt to add some white vinegar to the rinsing water for tougher stains.
- Use a dry cloth or towel to clean any remaining water and paste off the glass.
For mild hard water stains, you can use a lemon as your cleaning agent to treat difficult stains. Cut a lemon in two and then rub the cut side onto the glass and over the stained areas. If the stain is gone, rinse the area with cold water and dry thoroughly. Otherwise, you can move on to adding in one of the other cleaning solution methods.
Another method for cleaning hard water stains involves razor blades to remove the stains physically. This is a more labor-intensive method, but it can work on glass that is not tempered. You will need to be careful to keep the razor's sharp edge facing away from you. You will also need to be gentle when scraping the stain with the razer as you do not want to damage the glass.
Removing Hard Water Stains From Dishes
If you have glasses with hard water stains, using a rinsing agent in your dishwasher can help remove stains as well as prevent them from happening. If your rinsing agent does not work, soak the glasses in a bucket of 50% warm water and 50% vinegar for an hour. Remove them, rinse them off with cold water and dry thoroughly with a dish towel or cloth. Another method is to fill a dishwasher-safe bowl with vinegar and place it in the bottom rack of the machine. Then fill the dishwasher with your glasses and other dishes as normal and run the regular dishwasher cycle.
Preventing Hard Water Stains From Forming
The easiest way to handle hard water stains is to keep them from developing in the first place. If you have a house with hard water, you can investigate having a home filtration system added that can significantly soften your water. These systems can be costly, however. If you are on a budget, just being diligent about taking a towel and wiping excess water from your glass shower door, drinking glasses, and other glass surfaces regularly can help prevent hard water haze from forming. Hard water stains are easiest to remove with common household items like vinegar and water if you do not allow them to set in over time.