Hardness reducing chemicals ...
Published by Mohd Salman, Assistant Project Manager (Water & Waste Water Treatment Turnkey Projects)
Hardness reducing chemicals are basically phosphates & orthophosphates. They react with Ca, Mg & silica to form a water soluble compound. Antiscalant in RO used for membrane protection. Hardness makes up to TDS, as TDS removed during RO so hardness also. For ultra pure water, Nil tds you need DM plant. But if you want cheaper method ;can use water softener, practically u will achieve hardness 3-5 ppm.