Not sure what your asking here?
Big Bud is easy to grow.
Ph in water should be between 5.4 and 6.1, I found 5.9 is the sweet spot. Don't chase Ph pick a range and stick to it. I use the 5.4 to 6.1, if it goes outside of these numbers than I take action.
As it sounds like your new at this here are some words of wisdom on hydro and Ph , PPM.
If your nutes are at 500ppm and two days later there at 350ppm you need to up your ppm! It works like this change res set ppm at say 600ppm ph 5.9 run for 24hrs, now if you ppm rise and ph drops nutes are too strong. If ppm drop and ph rises, nutes are too weak. But if your ppm and ph are basically stable then you have found the right mix for your plants.