I dont know whats wrong!!!

a friend asked me to see if we can find out what caused this
i have little info from him,surprised its made it this long
3rd wk flower
ffof soil
temps 80 +/- 1/2 F
humid 50%
water ph'd to 6.5-6.8
the leaves are very brittle
started at the bottom, now heading into the new growth.
i wish i had more info for you.
i will keep on him to answer any ?'s brought up/
please help me out if you would.

Thank You

Who cares as long as the bud is ok fuck the leaves.

calcium deficiency. cal/mag would solve the problem. GL

U can also use dolo lime as a drench. That will give you cal and mag. It just takes longer to absorb. Epsom salts at 1tbsp/gal water can be sprayed directly on the leaves for fastest absorption of mag.