I just started using Intellichem to constantly inject chlorine to regulate ORP. For the last six months, I've been running with no daily chlorine at all, just weekly chlorine in the form of shock + constant ozone injection and copper ionization.
Right now my CYA is zero and the ionizer is turned off.
I figured I wait to add the CYA--this should require more work from the Intellichem and I want to see it "doing it's thing".
Intellichem regulated the ph down to my setpoint of 7.4 and ORP up to 700. ORP = 700 resulted in more FC than I want, so I've backed it down to 680 and will test again tomorrow morning.
The pool gets full sun and the last two days have been sunny, but today is cool.
I was expecting chlorine use of around a gallon each sunny day (17K gallon pool) after reaching the initial FC target. It seems quite a bit less than that so far, but it's too early to get an accurate measure. I'll know better after a week of use and daily (afternoon) FC measurements.
I think I paid $1.39 per 64 oz bottle of 8.25% bleach at Aldi. The canister holds four gallons. Before I add CYA, I want to figure the cost and required refill frequency if no CYA is used at all. Then go from there.
Are there reasons to use CYA other than reducing chlorine usage?