nutrient deficiency ?

hey there, this is magnesium deficiency. That's because the heavy light schedule and perfect environmental conditions are sending the plant's metabolism into overdrive and therefore it needs more magnesium to process the photosynthesis. Try cutting back the light schedule as much as you're comfortable with to reduce the light stress, then add cal mag in the feed every week as well as a in a spray usually 1ml/L will do and spray just before lights on twice a week for like two weeks. Do this and the problem should stop spreading within 10 days. Hope this helps ! 🚀