This Kinetico Signature series water softener system was installed in a home with a water supply of 30 grains of hardness (anything about 10.5 grains is considered extremely hard). This water supply had ten ppm (parts per million) of iron. Iron begins to stain when it hits 0.3 ppm.
Our competition would have had to install an iron filter alongside a water softener unit. But not with Kinetico!