It looks like the high ph is causing lockout.

I use General Hydroponics ph Down (phosphoric acid) 1 tsp:5 gallon bucket of water, brings my well water from 8.0 to 6.8 ph. (6.3 to 6.8 is fine) Lowers the ph, and the plants love the phosphorous.

A good flush with properly ph'd water would definatelly help.

With the yellowing fan leaves, troubleshooting can be tricky, as there's a few reasons to be considered. Like the water ph, the soil and runoff ph, quantity of N in the flower ferts or micronutes.

I agree with Divestoned, in that the nutes I use (Fox Farms) has enough N to keep fans green thru to harvest, but I do have to cure longer to remove those imputities.