Red edged leaves

And another one...... Look up '' Cannabis deficiency chart ''...... Good luck man.

Edit: I looked at your diary and you can see that the yellowing starts from the top instead the bottom up. Nitrogen is a mobile nute so that starts from the bottom upwards. You can see a starting deficiency of iron or magnesium. The more acidic the solution (ph) the more iron, and less mag. But you add the mag extra. In soil it's difficult to actually foresee the problem, this is different in dwc. You can measure directly the ph/ec and if in distress you can quickly change the reservoir with the appropriate values ;) Big hint!

Your npk ratio is off, or your PH is off. There is def a nitrogen deficiency, and otherwise it's a mag deficiency in combination with nute burn. So indeed flush with proper ph and check your npk ratio. Or your ratio is off, or your ph so there is a lockout.

This is the start of an Overfeed. I think thats more an orange colour lol but the postion its in on the leaf is definatly an overfeed im a dwc grower so its something im pretty familiar with when shes dry give her normal ph balanced water for a week then reintroduce the feed at a slight lower ec or ppm value and you should be alright :) Best of luck for the rest of the run :) 👊

I would raise your lights just a little more, and check your run off pH. I would guess the soils pH is out of the proper nutrient zone then flush her. After the flush give her a light feeding because you will have flushed the nutes out aswell