If your ph runoff is at 6.2 what is the ph in the res? Just curious because I believe hydro should be somewhat lower than that, like 5.7 or 5.8. I'm sure one of the hydro gurus can chime in on that.

I can see some lightening in the margins of the leaves when I look close up at the pics. I might be concerned as well, but look into your ph in some of the other logs and see where they are at. I would bet that is the issue because everything else seems locked down, temps good and all that.

Good luck.