Just saw this thread and skimmed most of it. Interesting differences to my coco grow, which is Sour Diesel from seed. In my case I've just lately crept up to an EC of 1450. Anything over about 1200 has some light tip burn so I've diluted my notes through mist of the grow. (Diluted by about 200 EC compated to the GH mid range chart.
My pH has been held constant at 6.0 throughout.
I've not changed much because the plants have grown like crazy and had very few issues.
I've just started week 4 in flower, and I'm still defoliating thick spots. My RH is holding at 54% with powered input fan and AC-Infinity output fan. Temps have been 78 to 82f throughout.
Fertigating 5x daily since a bit before flowering. Runoff EC was consistently much lower than input until 12/12 lighting change. It had been getting higher and higher before that, but it seems to gave jumped since then. I went from 800 points less to 800 points over input 5 days ago. I gave it a double feeding to flush it down a bit, and I went from 30 to 35 seconds each watering to make more runoff. EC today is about 100 points higher than input.
I'm sure hoping my buds will look as fat as yours soon. Sour Diesel supposedly takes an extra 3 weeks in flower, and they are getting very tall now. Including pots and risers the tops are almost 6 feet tall now.
What sort of issues did you have with your Sour Diesel grow?