Jason/Bill: Thanks for the input. I will make an attempt to do some testing this weekend hopefully. My idea is to try several methods. 1) to concentrate the solution as Jason suggested and test that; 2)preparing a solution with a measured amount of soda and testing that; will play around with it and try different things and see what happens. I have a friend who is a winemaker and has an electronic scale in his lab, so maybe one way or another I can come up with an approximation with some fair amount of accuracy. My main focus this weekend will be getting stucture together, although I would like to get my water quality thing in order soon as I will be stocking BG and fatheads within a month or so. Thanks all for your input.