Distilled water?

[TimmyR]

It doesn't matter. If you treat your mash water only, it could possibly drive the mash pH a bit too low, so then you could add the rest of the additions to the kettle or sparge water.

Thanks @Yooper. I used to have all this nailed down, but it's been a few years and its on a different set-up. I am pretty sure with the built water, a conservative efficiency estimate and solid yeast pitch we should be pretty successful. My neighbor is really wanting to make a good beer. We failed 2X before but I did not know his water was softened.

 

[Yooper]

Thanks @Yooper. I used to have all this nailed down, but it's been a few years and its on a different set-up. I am pretty sure with the built water, a conservative efficiency estimate and solid yeast pitch we should be pretty successful. My neighbor is really wanting to make a good beer. We failed 2X before but I did not know his water was softened.

I think you've got it pretty well nailed down now, using distilled water and a few additions. Let me know how it turns out- I'm very interested!