I should clarify my previous post.

what I put was Ca and Mg hardness. Using the formula on pg 158 I converted them to Ca and Mg ppm.

Ca = (125/50)=(2.5*20)=50 ppm (assuming Mg/L and ppm are roughly equivalent)

Mg = (39/50)=.78*12.1 = 9.43 ppm

so my Ca and Mg figures are 50 ppm and 9.43 ppm respectively.

Alkalinity is a different issues. My water treatment plant gave me a spreadsheet with the min-max and average figures for 2009 but they give me "P" alkalinity and "M" alkalinity. I have no idea what these are or if I should just add them together to get my total alkalinity.

Having said that, they also forwarded me a more complete spreadsheet, though a bit dated that had total alkalinity as CaCO3 as 72.

Hope that helps you help me

thanks