While water is the key to clean dishes, hard water is the biggest culprit of stains on dishes and glassware. Hard water is water that is richer in minerals than soft water, which is more diluted in minerals. Minerals in hard water include lime, magnesium and calcium. These minerals are not harmful to ingest, but they do present pesky problems for dishwashers. They're seen as whitish spots on glass and are most noticeable on dark dishes and clear glass. Those white spots are actually lime scale, residue left behind from lime deposits in the water.
If your water is hooked up to a city water supply, you won't be able to soften your water yourself. However, you can prevent hard water from leaving stains on your dishes by either adding a rinse aid to your dishwasher cycle or adding more detergent.
While spots and stains on your dishware may seem like a nuisance, it's fairly simple to find solutions for dishwasher issues. Taking proper precautions and using the right products will make for a successful and long-lasting relationship with your dishwasher.