How to lower Alkalinity without acid

[bearsprague]

Thank you for the information. I use a lamotte pro 9 test kit. I drained about half the pool and refilled it so I wouldn't have to use so much chlorine to shock. I added a quart of muriatic acid and the levels now are: FC-4.19, TC-4.27, PH-7.4, ALK-193, CH-27, CYA-33. I switched to liquid chlorine. I wanted to make sure the CYA levels wouldn't rise and be back where I started. The reason I wanted the alkalinity down was because of my pool heater. I didn't want to have scale inside of it. Do I need higher calcium because of the heater? What is the best way to aerate to raise the PH after acid: water fountain or air injected into the water? Thank you

[PoolDoc]

+ Hayward will tell you need CH > 100 ppm. I doubt that that's true, but it won't hurt.

+ With a heater, you do want lower ALK.

+ I don't know which would be more effective aeration; I believe either would work fine.