A composition of a treatment fluid and method for treating a zone of well. In an embodiment, the composition includes at least: (i) an aqueous phase; (ii) at least 5 ppm iron ion in the aqueous phase; (iii) a source of at least 5 ppm iodide ion to be dissolved in the aqueous phase; (iv) a water-soluble viscosity-increasing agent dissolved in the aqueous phase; and (v) a source of an oxidative breaker to be dissolved in the aqueous phase. In an embodiment, a method of treating a zone of a subterranean formation of a well includes at least the steps of: (a) forming a treatment fluid according to the composition; and (b) introducing the treatment fluid into the zone.