For well over 2 years now I have been battling terrible water spots on everything the water drys on, ie shower enclosures, fixtures, coffee caraffes etc. Local dealer and manufacturer have tried to remedy the problem but to no avail. I have paid for private testing that shows corrosivity and sodium in the residue that dries. Rainsoft says because their tests show proper numbers then the unit is working properly. They do say (and what sold me on the unit) was it is virtually spot free. It was working properly for roughly two years and then trouble brewed and we can't seem to get rid of the spotting. The salt content in the water is so bad it has etched my glass shower doors and aluminum rails and it has etched my coffee pots.Everywhere there is a water spot it will dry and leave a residue. Nothing we do helps!