Method of Lowering Total Alkalinity without hardly affecting PH that I found

[chem geek]

What are you using for testing the TA? Are you using a Taylor K-2006 test kit? Did you turn on the pump and remix your water before measuring the TA again? Did you mean Muriatic Acid instead of CYA? Did you mean 1-1/2 gallons instead of 1-1/2 cups which would hardly be able to be poured in multiple places into columns?

To actually lower the TA from 190 ppm to 100 ppm in 24,000 gallons would take about 4-1/3 gallons of full-strength Muriatic Acid (31.45% Hydrochloric Acid) and it would not matter how you added it, the TA would drop by the same amount. The difference would be in what happens to the pH and in damaging pool surfaces.

You could very well have added 1-1/2 gallons of Muriatic Acid and if you added enough in one place with the pump off then the TA in that place can certainly drop a lot, even to 100 ppm, but that is not the same thing as having the TA drop everywhere in the pool by that amount. Measure the TA again after turning on the pump and thoroughly mixing the water. 1-1/2 gallons of acid would lower the TA from 190 to about 160 ppm in 24,000 gallons.

[CarlD]

This is nothing more than the discredited "Column" method of T/A lowering.
Frankly, I find the method and results difficult to accept, and chem_geek and waterbear are two of our best on T/A chemistry.

Are you sure of your chemicals and how you ran your tests? When pH drops, TA does as well, but a .3 drop shouldn't be enough to resolve a TA difference of 190 down to 100.

Carl