From an anonymous contributor:
Our dishwasher has been delivering a scummy finish to all glassware for about a month. All investigations, repairs did not fix it. I overheard someone in line at Safeway talking about Los Altos hard water and found this link.
I called CalWater and asked what the hard water measurement in Los Altos will be for the duration-“18/23 grains”, fixed by late January. Based on this link:
What to do? I went to True Value hardware in Los Altos. They recommended Finish Glass Magic, then told me they were sold out. There were three more people there with the same issue. I found a box at Ace hardware in Palo Alto (OSH, Wal-Mart, Safeway all came up empty), tried it, works as advertised.
I just checked the recent water bill, zero commentary on this. I have come to the conclusion that CalWater is a member of the Dishwasher Industrial Complex.