3 weeks flowering, leaves turn yellow, gray then die?!

Hi All!

I know that it is normal for the plants to lose SOME fan leaves near the end of flowering, but I'm only a third of the way through.

I have 7 girls from bagseed growing in soil. 23 days since start of 12/12 and flowering nicely. Feeding Age Old Grow and Awesome Blossoms (each at 1/4 strength for a combined 1/2 strength solution). Occasionally add Cal-Mag with added dolomite lime to balance out pH. Room stays between 74-82 F and around 20% rH, sometimes gets up to 60% with humidifier on. I've been feeding about once every 7-10 days.

Is this a nutrient deficiency or something else?

Thanks a lot for your insight!

Anybody? Does this look like a fungus or a nute deficiency? Or nute burn?

Just from my experience, looks like over fertilization. Skip a feeding and just water. You should trim all of the damaged leaves out. When you resume feedings, go about 1/2 the rate you are currently using. Make sure that you are feeding when the soil is moist also. Feeding when the soil is dry will burn them bad too. I used Super Bloom (12-55-6) and had great results but I had to be careful with that shit! I little bit goes a long way with these plants!