She is beautiful. She is a monster in the making! The reason you have to chase the PH so much is due to her sheer size. Her root mass is substantial and that means less water will fit in the reservoir. Now there is maybe 2.5 - 3 gallons of mix in the reservoir. Less water more roots = faster changes. Did I mention before that hydroponics requires the most time from a farmer? She will be worth the effort.