black veins

My leaves are turning yellow and black veins in the fan leaves. Is this from lack of nutes?

how about some info or pictures

lack of specifically:

Iron: Leaf tissue appears yellow, while the veins remain green...

just raise your nute levels, check ph

and for fucks sake, read the faqs.

https://www.rollitup.org/marijuana-plant-problems/38772-guide-diagnosing-plant-problems.html