It appears that the Pool Calculator does not take into account the Borate level when calculating the dose of muriatic acid required to lower pH. Does someone have a formula to make the adjustment. I have about 50 ppm borates and the amount of acid required is Much larger than computed with the pool calculator. This is confirmed by both the acid demand test and results in the pool. I had very good agreement with the pool calculator dosing and acid demand tests prior to adding the borates.