I don't know that your CYA level actually has an effect on where you keep your pH level--it's Cl that definitely needs to be higher with high CYA levels. As far as pH goes, 7.9 is on the higher end of "normal", but if that's where your pool likes to stay, then you can leave it. Sounds like you're making huge progress in lowering your CYA--wow--330 was a lot!
Your calcium should lower with the draining/refilling you're doing, unless you're using cal-hypo to chlorinate/shock with. A hardness of 239 is fine in a vinyl pool, but if you get it too much higher, your high pH and high TA may cause some scaling if you have a heater or other equipment.
Janet
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