A method of warewashing is provided. A combination detergent rinse aid composition is used according to the invention. The warewashing detergent composition includes an alkaline source and a water-soluble anion. The rinse aid composition comprises an acid. The alkaline source is provided in an amount effective to provide a use composition having a pH of at least about 8. The anion is present in sufficient amount to leave a residue of anions on the surface of the wares. The acid of the rinse aid has a sufficiently low pKa to react with the anions to form an insoluble oxide on the surface of the wares. The insoluble oxide reduces the surface tension of water on the surface of the wares thus reducing water spotting. Methods for using and manufacturing a combination warewashing detergent-rinse aid composition are provided.