Hi
@Akvinsky ,seems to me to be a magnesium deficiency.i've been looking at your diary and even at the lowest part of the plant far away from the led are leaves with dry tips and curls upwards, this is a lack of mg.If there is an accumulation of mineral salts in the roots of your plants, you can calmag or epsom salt every day that it will not be able to feed on the calcium and magnesium you give it. you have to make a flush 3x of water the liters of the pot and apply a good corrective dose of calmag. if the problem persists you will have to apply a soil cleaning solution (florakleen or ata clean per example) and then apply calmag or epsom salt. good luck mate 👍🙏💪