Well back to the topic of finding the sweet spot
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 to strong. If ppm drop and ph rises, nutes are to weak. But if your ppm and ph are basically stable then you have found the right mix for your plants.
[FONT="] Then when topping off your res use pre mixed nutes to keep it at that level, if it starts to rise or fall adjust top off nutes as needed to bring it back to proper level. This is how I set my system up and has worked great for me.
The other thing I don't do is chase ph, I pick a range that is suitable for the way I am growing and leave it at that. For example in my RDWC System my range is 5.4 to 6.2 when it moves out of that range I take action.
IMHO
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