I've always (with good good results) prepped 10 gallons of water for my 5.5-5.75 gallon batches and calculated the final mineral content based on my final fermenter volume...something like this ...7.59 (pre-boil) / 5.5 (fermenter) * 58 ppm CL (10 gallons treated water) = 80.04 ppm CL (finished beer) I can't help but think I could simplify my process by plugging in my mash water volume, but subtracting my grain absorption and boil off volume from my total sparge water volume, then adding my mash salts giving me my final mineral content based on the fermenter volume...something like this for a beer I'm planing Total Water: 8.8 gallons Mash Water: 4.1 gallons Sparge Water: 4.78 gallons - 1.29 gallons (grain absorption) - 1.84 gallons (boil off) = 1.65 gallons entered for sparge volume. Giving me a total of 5.75 gallons in the fermenter. Am I completely off here? Am I going in the right direction? Am I missing something?