So very true. Been growing since I was 21, last 10 indoors exclusively, now 58, so that is .... wow, like a lotta years, and I still learn something new every plant that I grow. Love to experiment.

I will say this though, I used to say the same thing about not worrying about the PH. I found myself wrong and my water source (city water even) can fluctuate greatly in 24 hours. Last week for example it was running 5.5, then it rained hard, and overnight the PH went up to 8. I took 3 days for it to come back down to the usual 6. I RO my water to remove excess Iron.

So, not sure about the ppm stuff as I soil, but PH can be a real problem for some folks. It took me 5 years to figure this out, by the way. And, yes, those companies are out there to sell nutes. The less I use the better I grow.