100% RedX mash with RO water should come in around 5.3 pH without adjustment, at 1.5 qt/pound. My DI test mash before I brewed put it right at 5.29 pH. I used the DI to calibrate to the 15L rating, as that is the only mechanism to adjust malt acidity (as far as I know) in Bru'n Water. There is...