This article helped me understand how pH changes due to nutrient uptake.
"As the plants absorb these nutrients through their root systems, the system slowly loses its acidity to become alkaline. Over time, the pH numbers will gradually rise until you add more nutrients."
My experience as a grower is limited - one grow three years ago where I tried to “fix” pH. After issue and a couple of other issues, I archived the tent until this year. My current grow has had none of the pH “problems”. Nute burn is in indicator that the TDS is too high so, when we see leaves starting to yellow, we drop the TDS of our nutes. Similarly, dropping pH could well be an indicator that the TDS is too high (another cause is root rot but, from what I’ve read, it’s easy to tell because the roots smell awful and pH plummets rather than dropping slowly).
I’ve attached what I refer to as the Wonder Chart and, also, Son of Wonder Chart (the latter is found
here). I’ve followed these two charts religiously and, in the 94 days of this current grow (4 Gorilla Glue autos in a large RDWC res) the only issue that I’ve had was when I sprinkled a few drops of nutes on a few leaves. Other than that, the foliage has been “picture perfect” - the opposite of my 2017 grow.
HTH
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