Kids swam all day. We also had 2 guests over swimming.
I added 1/2 inch of water to pool. Let it circulate for an hour. Added 26 oz of chlorine to get my fc to 8. Tested st dark 1 hr or so later. It was 8.
When I got up at 530. Not totally dark. I tested 4 times. 7, 7.5, 7.5, 7.5.