I filled my pool (13400gal) with well water and the ALK is at 400, PH 7.6. I know that I have to lower the PH to 7.0 and then aerate the water to bring the PH back up. Is there a formula I can use to calculate how much acid I need to lower the PH to 7? I am using the bleachcalc app but I am assuming that I will need a lot more acid since the ALK is so high. I could just add small amounts until I get to 7 but since I'll have to repeat this process many times it would be nice to add the correct amount the first time. Can someone help me out?