Sodium Hexametaphosphate is also called as Calgon. The formula for Sodium Hexametaphosphate is (NaPO3)6. It is a gathering of sodium polyphosphate polymers based on repeating NaPO3 units. It is a water dissolvable polyphosphate glass that comprises of circulation of polyphosphate chain lengths. Sodium hexametaphosphate is a complex phosphate glass produced by a thermal process from soda ash and food-grade phosphoric acid.