two weeks frm harvest and leafs turns brown and dies.

Hey everyone Idk if u can get me out here. I'm two weeks frm harvesting and some of the leafs are turning brown and dies. Here are ssome of the info. Pix will be up later.

Ppm- 900-1010
Ph-5.8 ( hydro)
Temp: 82-85 degrees ( night) and 65-70 degrees ( lights off)
4-1k aircool hood with carbon filter

Btw current nutrients are
Gh- 3 part
Kool bloom
Floraliouss bloom
Big bud

to a certain degree this is completely normal towards the last couple weeks of flower.

may be overdose of koolbloom. very easy to murder plants with 1/4 teaspoon too much