Leaves dried up and crumbling

4 weeks ago I got a bit of nute burn and the tips of my fan leaves browner and crumbled off. Now, all the fan leaves are dry and brittle and light in color. They literally will break or crumble if you bend them. After the slight burn, I flushed twice and it's had ph 7.0 water for a month now no nutes. Don't have pics right now but any ideas? It's also showing no nitrogen deficiency

Bagseed
day 97 flower week to go
400w hps
temps 77
organic soil
ph good

day 97? you sure it ain't over ripe? if its bag seed you cant really judge flower time till its ready. temps a little high