I'm confused about the chlorine additions. I had been using a calculator at another website that seemed to be working well. It told me to add 83 oz of 8.25% bleach to get from 10.5 to 15. So I just plugged my numbers into your calculator and got 86 oz. Please show me how you calculated that 80 oz would raise my level by 16.3. Also, I see I have full access now, so I will go enter all my pool details into a signature. But just to make sure we're on the same page, my pool size is 12,300 gallons. Maybe you used liters?