I can't seem to find this deficiency anywhere

Small tent hand water coco

Bigger tent wilma system with hydroton/pebbles


Temps have been 24-31 (hot summer)
RH 45-60%
plants are 2 weeks 12/12
PH 6.1-5.5
ec 1.6
Background ec 0.7


This happened on my last grow too (my first) It stunts them from growing colas all I got last time was pop corn bud all over, no colas at all. always seems to happen just after I switch to 12/12


this small tent is day 20 12/12

It starts out like this, as if someone has rubbed lightly with sandpaper.





I tried some calmag in the wilma, ½ ml per L. still didn’t help. I really an at a loss.

I also changes nutes from hessi on my last grow to AN ph perfect sensi

This is the bigger tent as you can see it gets a lot worse



Big tent is under 600w hps
small tent 300w led, 250w cfl

Really could use some pro help here.

Heat stress, I had to do some converting but ideal temp for you would be 25-26 celcius, at 31 (when lights are on) you're cooking them girls. 27 is as warm as I would ever want to go, that said I'm with ya running between 29-31 during lights on. You also probably need a bigger inline fan to remove air from your tent, thats my fix.

Cheers but my last grow the temps were not that high and I had the exact same thing, always seems to happen a couple weeks after I flip.
I have 6" extract in 1.2 tent, big oscillating fan through the canopy. I'm really not sure anymore, Ive about given up on growing.

Looks like a P def.

Check out this thread.
https://www.rollitup.org/marijuana-plant-problems/488004-guide-nutrient-deficiency-toxicity.html

I got same issue on a few leafs with leds but nutrients and ph fixes it