A bit confused

[chem geek]

Yup, you got it. Aerate until you get to around the 7.5 pH that you want. Add CYA to around 30 ppm which should be fine. This graph shows that the biggest bang-for-the-buck comes from very little CYA. At 30 ppm, you would keep your chlorine at a target of 3.5 ppm (absolute minimum 2.5 ppm) and your chlorine half-life in direct noontime sun should be about 6 hours (so in practice that means losing somewhat less than half your chlorine level in a 24-hour period). So you might add chlorine at night to get to 7 ppm and find it down at 3.5 to 4 ppm the next evening. At 50 ppm, this half-life increases to about 7 hours, but you'd then need to have a chlorine target of about 5.7 ppm (absolute minimum 3.7 ppm) and you'd end up adding more chlorine to maintain this higher FC level.

Using a pool cover will significantly cut down chlorine usage. Using 30-50 ppm Borates may cut down the usage as well since the Borates will kill algae so that chlorine doesn't have to. Actual chlorine usage is also a function of how much junk (organic matter) gets into your pool. And of course, a pool party with lots of little kids who just can't "hold it" (or get out quickly enough) will use up a whole lot of chlorine very quickly.

Richard