Over watering will increase your root zone ph overtime, 95% of the issues are due to incorrect ph in the root zone(gradually).
you can feed plants with 1.0-1.2ec (500 scale) for a really long time.. so I doubt its deficiency but again depends on what nut line and genetics you're using/growing.
to me, that looks like a start of Mg (also caused by too much water or cold feet also if too much cal) let us know how they're doing now a week later.
Happens to me sometimes also and it just corrects itself when the plants mature.
Absolutely on the money across the board. I had upped to lots of small waterings instead of a couple of big ones a day, and was basically drowning the roots. In addition I EC tested my tap water - fucking 0.7. And the water authority has tested it, it's not free calcium, it's all carbonates and pipe sediment, basically the sort of shit that takes up sites for alkali metals and locks them out. Definite Mg issue as a result. I've posted pictures of leaves on other threads where you can see the point where the issue stopped actually in the early and late growth of the leaf.
Have switched to RO, 0.7 is ridiculous. I'm now able to give them 1.8 that is all nutes, rhizo and a bit of
Calmag which is making all the difference.
Thanks for taking the time, and being so damn on the money. By the way pH out is back to 6.2 and I'm getting 1.6 out which is slowly climbing, but within 0.3 of input so I'm happy. Some day 37 pics. Hard to believe these are only a week older than those pics. They are exploding after topping. You can see the darker colour of the new growth, not lacking anything I can see.
