Patent ID: 8685257

Claim:
A method for controlling microbial growth in potable water stored in a vessel having a metallic surface, the method comprising: heating the metallic surface of the vessel to a temperature between about 480Â° C. (900Â° F.) and about 870Â° C. (1600Â° F.), wherein the metallic surface comprises nickel; exposing the metallic surface of the vessel to oxygen during heating to oxidize potential reduction sites on the metallic surface; treating the metallic surface of the vessel with a solution containing an oxidizing agent after heating the metallic surface and exposing the metallic surface to oxygen; and charging potable water containing an initial concentration of silver ions to the vessel, wherein the oxidation of potential reduction sites on the metallic surface causes potable water stored in the vessel for about 110 days to contain a concentration of silver ions not less than 84% of the initial concentration.