Tonedef: is that information published anywhere? I would love to see it. I have been thinking of doing the same thing. My city water can come from any of 3 sources that feed our grid, each with a different profile. I can have a brew come out well one time, then not taste right the next, and I suspect the water is the uncontrolled variable that is making the outcome too random. I would be thrilled not to reinvent the wheel in the process of doing this. Would you mind to post your tables, or point me to someone who has?