Its got me fucked atm lol..i dont really get these problems to learn...could b too much one one thing maybe locking out another...32 tomorrow and 40 deg celcius the nxt..b interesting if they get abit of heat stress ..
In the pic where you circled the leaf/leaves (along with the others) I see chlorosis in the young top leaves. Top leaves showing intervenal chlorosis, then moving to the mature leaves, and starting at the leaf base moving out to tips, indicates iron deficiency according to the book. The thing is your pH appears to not be causing an uptake problem, so that would leave and actual soil deficiency or lock. If it is iron. Maybe it's a good idea to get that pH down slightly anyway since the two sick ones do have a higher pH than the others. It would probably be good to do a chemical pH test as well before adjusting anything.
I'll keep looking and see if I can hunt down any other reasons. What about soil pests like nematodes? What were your temps the last week?
It took some work to see the broad Mites that infested my girls even with a 60x loupe. They were well hidden among the hair-like trichomes. Just a thought since were banging our heads against a wall.
We'll figure this out brother.
