For really tough hard water stains, try scrubbing with some hydrogen peroxide. Yep, the same stuff you have in your first aid kit. Hydrogen peroxide plus some elbow grease should banish even the most stubborn of hard water spots from your metal fixtures.
So, hydrogen peroxide, baking soda, vinegar, and toothpaste are all effective at removing hard water stains from your house.
It is also widely used in horticulture. It is a versatile product. In addition to disinfection, the use of hydrogen peroxide helps to remove limescale and corrosion.
Calcium buildup can be removed from coffee makers and coffee pots using everyday household items such as vinegar, lemon juice, baking soda, and hydrogen peroxide. Mix them with water, let the solution sit, or run a few cycles through your coffee maker to dissolve calcium in 20 minutes or less.
How to Remove Calcium Buildup. White vinegar, baking soda and even a lemon can be used to get rid of pesky calcium stains. Many homemakers already use vinegar to help clean difficult areas. It's also helpful when addressing hard water stains or calcium buildup.
Hard water deposits are alkaline, so an acid-based cleaner is the best way to clean them. Phosphoric acid works well and is safe for most surfaces. Grocery store cleansers with phosphoric acid contain 4 to 6 percent acid.
If you notice brown stains, limescale, or other unsightly mineral deposit buildup in your bowl, pour about a cup of hydrogen peroxide directly into your toilet tank. The chemical's bleaching properties will dissolve stains and sanitize the tank without damaging the flapper or flush valve.
Vinegar. Because vinegar is acidic, it's one of the best hard water treatment options for clearing out scale buildup in your tub and sink. You can even use it in your appliances, like your coffee maker, dishwasher, and washing machine, to help them function better.
Hard water can be softened by adding sodium carbonate (washing soda) or by passing the water through an ion-exchange column.
A paste of baking soda and hydrogen peroxide cuts through soap scum and hard water stains on tubs and tiles.
When injected into water, hydrogen peroxide releases a large amount of dissolved oxygen which has a strong oxidizing effect, destroying odors and oxidizing iron and other contaminants. Hydrogen peroxide does not add chemical by-products into your water, only oxygen and water.
Clogged drains are unpleasant and can smell bad. Hydrogen peroxide may already be in your medicine cabinet, and it is gentle enough to use in your pipes. If you notice your sink draining sluggishly, you can reach for a bottle of hydrogen peroxide instead of a more expensive chemical drain cleaner.
Unlike chemical drain cleaners, hydrogen peroxide won't destroy your pipes and drains. It is safe for regular use so you can do a hydrogen peroxide flush once every few weeks to keep your drains and pipes in good shape. However, for more complicated issues, it is always better to call your plumber.
Hydrogen oxide (separately, a great cleaning agent and antiseptic), if mixed with vinegar, creates peracetic acid, as vinegar contains acetic acid. This combination of vinegar and hydrogen peroxide is potentially toxic and corrosive, which can break down or damage the surface it is applied to.
However much you are making, just add twice as much hydrogen peroxide as you do the detergent. So for a small stain mix 1 teaspoon of Dawn with two teaspoons of peroxide. For a large batch 1 cup of hydrogen peroxide to ½ cup detergent works!
Hydrogen Peroxide and Vinegar
“Combining these two creates peracetic acid or corrosive acid, an irritant that, in high concentrations, can harm the skin, eyes, throat, nose, and lungs,” says Bock.
Hydrogen peroxide used to be a popular antiseptic for cleaning wounds and treating acne. But it's not a good idea to use it for those purposes, since it can irritate your skin. If you don't want to throw away your brown bottles, you can use hydrogen peroxide to clean and disinfect around the house.
Citric acid
More importantly, it's probably even more effective than vinegar for getting rid of that brown stain in the toilet. Simply pour a kettle of almost boiling water into the bowl, follow up with 250ml of citric acid, and leave it for some hours – preferably overnight. The next day, scrub and flush.
Clean the grime off your tub, shower or tiles
Use Dawn and some hot water and a cloth or sponge to get into those nooks and crannies where grime and scale tend to build up. You can also combine Dawn with vinegar for stronger cleaning power, especially when tackling hard water stains.
Soften your kitchen water by boiling: Boiling will make the salts in water sink to the bottom of the boiler. You can then scoop out this water or pour the water in another pot leaving the deposits in the end. Install an ion-exchange filter to your kitchen faucet or use a water pitcher filter.