The most practical approach ...
Published by Thomas Getz, President at Earth Cycle BioTechnologyLLC
The most practical approach is to collect a representative sample and titrate it from your starting pH to your target end point. This will work for upward or downward pH adjustments. This will be more accurate than any mathematical estimate. The lab equipment for titration is inexpensive and an experience technician could deliver a result in 15 minutes. After this determination of the amount of acid/base required to effect a unit change in pH you can extrapolate to your full scale operation.