... .0% min Inactive phosphate, as P2O5 ------7.5% max Iron, as Fe ------------------------------0.05% max pH of 1% water solution ---------------5.8 ... .0% min. Inactive phosphate, as P2O5 ------7.5% max. Iron, as Fe ------------------------------0.05% max. pH of 1% water solution ---------------5.8 ... with metallic ions such as Ca, Ba, Mg, Cu and Fe Use: 1. Technical grade: Used in such industries as oil ...