Note: Beware of claims that water softeners give spot free results. All water softeners that are regenerated using salt will remove calcium, magnesium and some iron but they won’t remove all of the “TDS” (Total Dissolved Solids) so they will leave some spots. In order to obtain spot free results, the water has to be both “softened” to remove hard water minerals and “deionized” to remove the “TDS”. This is done by using both softening and deionizing resin and the deionizing resin can’t be regenerated with salt water so it needs to be replaced. If you need spot free results, the Softener Deionizer will do the job!