I don't know if this will help you or not. I'm using CO2 to adjust ph and it's been working beautifully. To ph down I add CO2 and water. I bought a soda club soda maker. To ph up I add ro or tap water (that has been standing to get rid of chlorine). My ph stays real consistent and I only ph adjust once a day. Sometimes I can skip a day. But generally it's once a day.

Plus I got a milwaukee meter that mountain man recommended and it's great. I just put the probe in the nutrient solution. At a glance I can determine if I need to ph up or down. Very simple.