Ok…I’ve put 3 so far and didn’t quite do pencil thin. Will do on my last twoIf your CYA is 50, your FC is 2.8, then you need to add 4 Gallons of 12.5% LC...or 5 gallons of 10%.
Yes, all at one time. Pour slowly in front of a return (pencil thin stream)...should take about 2 min per gallon. Brush around a bit after each gallon.