Oh boy, I might have missed the point. Is Calcium Hardness important in indoor liner pool with heater ? I have not raised CH "probably 40-50 in local water supply?" and with all the TA and FC just missed Ch as an important piece or not.

Please advise what I should aim for?

I do have a gas water heater too,
liner type
temp 89 deg F

FC 3
ph 7.6
TA 80
CH 40 ish "county water"

no CYA as indoor type

moving toward a BBB maintenance plan... slowly as I learn. Pulled out SWG and nature II in my history.

Thanks