Chlorine consumption sounds about right. What is your CYA level now?
Also, what is your TA? Is your pool plaster new, and curing, or is it older? This thread has gotten so long I can't remember the details without reading the whole thread. If plaster is curing, then the pH is going to rise as part of the process. If it's older plaster, and your TA is high, then you might try lowering it to around 70 and see if that doesn't make your pH more stable. Also, if you have a fountain, waterfall, or other form of water aeration in operation, that would contribute to the pH rise.
Janet
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