Discrepancy of MA/PH calculation on the old poolmath webpage

[ShinDiors]

Just noticed some discrepancy for adding MA to change PH value on the old calculation page: PoolMath

For example, for 18k gal size, using the calculation of Ph adjustment, from 8 to 7.5, it says 25oz of 31.45% MA

However, from the bottom "effects of adding chemical", add 25oz of 31.45% MA only lower Ph of 0.33,

Which number should I reference? Thanks

 

[cowboycasey]

the bottom area only uses the gallons of water... the upper portion takes in the affects of everything else.. Use the top area