New pool owner, trying to get my chemicals balanced

[PoolDoc]

I need to update the Best Guess page, to use a more % based dosing.

However you cannot follow the dose curve all the way down to 0.1 FC at 0 CYA, because of the fragility of very low FC residuals: any sunlight, and almost any chlorine demand will eradicate the residual, leaving the pool unsanitized.

Also, chlorine + UV is much more effective at destroying organics and complex chloramines than chlorine alone.

The kinetics of the Cl-Cya molecules is such that, when you have a HIGH CYA level, there's is a functionally limitless reserve of 'true' FC available. This is a factor I need explain more clearly on the Best Guess page, too.