Methods of reducing the viscosity of a viscosified treatment fluid; providing a clean-up composition comprising a carboxylic acid; a chlorite-based breaker system comprising an alkali metal compound and an activator wherein the activator comprises a metal and an amine. Placing a viscosified treatment fluid in a subterranean formation via a well bore penetrating the subterranean formation; first contacting the viscosified treatment fluid with the chlorite-based breaker; and then contacting the viscosified treatment fluid with the clean-up composition; and, allowing the viscosity of the viscosified treatment fluid to reduce.