Whyy??!

Yellow leaves can show a variety of defects. Overwatering – As the leaves wilt, they become wet and mushy. Underwatering - The leaves will shrink and look dry and crispy. pH problems - do you messering youre water? Nutrient blockage and nutrient deficiencies - - Yellowing of the leaves on the outer edges and veins (magnesium) - Yellowing of the leaves at the base and towards the tips (sulphur) - Yellowing of older, lower leaves, migrating upwards (nitrogen) - Discoloration that starts at the tip of the leaf and travels inwards (phosphorus) - Fading and "burns" (potassium) - Brown spots on the upper fan leaves (calcium)

Seems like to much water+ to much light + Boron Deficiency