I am using bleach for chlorination and muriatic acid to reduce pH. My question is

1) At what pH do you adjust your pH down
2) How low do you take it when you adjust the pH
3) How frequent do you adjust your pH

I seem to be adjusting mine from 8.0 down to 7.4 about once a week. In past years I don't recall having to adjust it this frequent. Below are my specs.

FC 2.0
TC 2.0
pH 7.8
CYA 30
Alk 80
Ca 20