There are numerous household products that remove hard water spots from glass, including white vinegar, baking soda, toothpaste, dish washing detergent and cola. It is also possible to use commercial products such as steel wool and general window cleaners to effectively remove hard water spots.
Among the most effective methods of removing hard water spots from glass is a 50/50 combination of white vinegar and water. A person combines the solution in a spray bottle and sprays it over the affected area, using a clean towel to wipe it down after each spray. Once finished, he rinses the glass thoroughly with clean water, uses a squeegee to remove excess water and then dries the glass with a clean cloth.
Another good removal product is baking soda. A person mixes the baking soda with water to create a paste and applies it to the affected area. He wipes the area clean with a dry towel and then rinses it thoroughly to complete the task. Toothpaste and dish washing detergent can be used in a similar manner to equal effect. It is also possible to use a towel or cloth soaked in cola to remove hard water stains from glass.
Alternatively, commercial window cleaner designed for hard water stain removal is located in most department stores. A person sprays the window cleaner on the affected area, wipes it down with a soft cloth and repeats if necessary.