© Tua Engineering Ltd. Malta 2010 An alternative to water softening is an automated chemical dosing system using  Polyphosphates. Polyphosphate feeders work by having housing units with polyphosphate  crystals inside where the water flows through, dissolving the crystals. The polyphosphate then  coats itself around the iron, calcium and magnesium in the hard water. This will then prevent  the usual problems that we run into with hard water.  Our feeders are available in a variety of sizes.  We can also provide standard cartridge filter hosuings with a polyphosphate filling. A WATER TREATMENT COMPANY