Method of minimizing pitting corrosion at temperatures above 130° C., wherein said method comprises: providing an acidic fluid comprising an alkylsulfonic acid; providing at least one corrosion inhibitor compound comprising an organic compound comprising at least two aldehyde functional groups; combining said acidic fluid with said at least one corrosion inhibitor compound; exposing said mixed fluid to a metallic surface at a temperature of at least 130° C.; and allowing said mixed fluid sufficient time of exposure to a metal to accomplish a pre-determined function.