Leaf discoloration... having a hard time deciphering it.

Hey there Thano, you have magnesium deficiency. That's because you have a pretty heavy light schedule, so the plant needs more magnesium to regulate its photosynthesis. You absolutely need to add cal mag, and you're not gonna like hearing this, but you also would do quite well reducing your light schedule as much as possible. If you treat the symptoms as well as the root cause the problem will stop spreading immediately and the plant will recover in 5 days... if you want to test the light schedule another thing you can do is a cal mag spray. Absorption through the leafs is much greater than through the roots , so try spraying just before lights on for best results. hope this helps ! 🚀

Hello on the last photo on your diary we can see clearly the beginning of calmag deficience with also beginning of potassium deficience. So for this use liquid calmag or epsom salt . you can use it in foliar spray for a quicker effect. Then increase just a little your nutrient dose to better feed your plant with potassium to support the flowering. Good luck. Bye

The problem is most likely the light is to intense. Dim the light a little and see if that helps.