Iron or Ph problem ( or other )

Colleagues do you think iron deficiency or a problem with PH or something else, one of the flowers is pale (white) all leaf's ..
2-3 times a week fertilize with Hesi (which reduce PH) ,bloom 50ml / 10l / booster 25ml / 10l and super Vit 2 drops; watered with a solution of 10 liters per flower, sizes range from 180 to 230 cm ....

im not sure but it looks like in might be a Sulfur deficiency from lock out. when you get the PH in range you shouldnt need to fertilize more than once a week. too much will cause lock out.

Youre feeding it way to much. Its most likely nitrogen toxicity

Thank you guys ! only water next 3-4-5 days