I’m the pool operator at our local YMCA and keeping an 80,000 gallon pool balanced is pretty easy, once you all the elements in place
and know what you’re doing.

Chlorine 3.5-4.5, alkalinity 80-100, ph 7.6-7.8, not 7.2, hardness 150-250, not up to 400.

You have to stay on top of it because the chlorine can go down in a matter of hours if no one properly checks it.