Phosphatase Acids are effective chelating agents as they tightly bind to di & trivalent metal ions, which is beneficial in water softening. In this way, they help in the prevention of formative insoluble precipitates (scale). These ligands binding also suppress the catalytic properties of metal ions. They are stable under harsh conditions. For these reasons, an important industrial use of phosphonate acid is in cooling waters, desalination systems, and in oil fields to aid in the inhibition of scale formation.