One gallon of Formula 2000 will treat 125,000 gallons of well water with 1 ppm iron and hardness of 15 grains per gallon or more. It is made for use with hard well water and for irrigation applications only. The “hardness” of well water creates an extra burden for a chelating agent as it treats iron. Formula 2000 is made of components that compensate for inorganic materials other than iron. It is the most chemically “efficient” product we make.