Hard water refers to that water which contains a high level of magnesium and calcium. When the water repeatedly comes into contact with a surface, the dissolved minerals form a build-up causing gradual staining of the surface. These surfaces may include sinks, bathtubs, shower, cookware even shower doors, bathroom vanity basins and basically any other place which has a constant stream of water. This stain is called a hard water stains and although not dangerous, it can cause a permanent damage to certain surfaces and should be removed quickly if spotted.
The question most people ask themselves is how they can remove the ugly stains from their homes. The first solution is to use a cup of vinegar and lemon solution mixed together. You should apply it on the affected area with a piece of wet cloth and allow it to sit for a few minutes and then afterwards, you can remove and rinse it. This solution should not be used on marble as the acid will etch the marble surface. Cleaning hard water stains can be made with professional products as well. These cleaners can be used depending on the type of surface maintained and one should always follow the instructions given.
But apart from just cleaning and removing hard water stains, it is good if you prevent your doors or windows from ever getting stained again. Areas which are used frequently should be cleaned with a mild detergent to remove any stains that might have started forming. Also you can teach your children to always dry the sinks after using them and also using warm water to rinse down such areas, after which you can dry them with a clean dry cloth to make sure that there are no minerals left over. Pay close attention mostly to the drains and fill lines as these, more often than not, have the highest potential of getting stained. Water softeners can be purchased to be put into the water storage tanks, as they change hard water into soft water thereby preventing the stains from recycling again saving you a lot of trouble cleaning.