How do I remove water spots from matte paint or a matte wrap?

Act quickly, because water spots cannot be polished out of matte surfaces. Fresh spots can often be removed with a matte-safe detail spray or a mild water-spot remover approved for matte finishes, applied with a soft microfiber towel and wiped without rubbing. Etched spots on matte paint or vinyl are usually permanent. Drying matte cars thoroughly after washing and rain is the best prevention.

References
  1. Hardness of Water, U.S. Geological Survey
  2. The Physical and Chemical Properties of Water, Drinking Water Inspectorate (UK)
  3. Hard water, Wikipedia
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