1. Are you growing from seed or clones?
Seeds
2. How old are your plants?
8 weeks
3. How tall are your plants?
20 to 24 inches
4. What type of hydro system are you using?
Dwc
5. What brand/type of nutrients are you using?
Gh trio, calmag, Epsom salt, silica blast, hygrozyme, southern ag
6. What is the Ph of your nutrient solution?
5.3 to 5.8
7. What is the PPM/EC of your tap water?
0 using ro
8. What is the PPM/EC of your nutrient solution?
570 after adding 1 gallon of plain ro
9. What is the temperature of your nutrient solution?
62-64 f - this has been adjusted to 72 f
10. Does your PPM/EC show a rise or fall when you do your daily PPM check?
Yes, dropping about 30 ppm per day- this went up about 30 this am, water consumption about 1 gallon
11. Does your pH show a rise or fall when you do your daily check?
Yes dropping .2 per day
12. Do you foliar feed or spray your plants with anything?
No
13. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights")
Hps 400 watts dimmable 1000 ballast
14. How close are your lights to the plants?
42-46000 lux
15. What size is your grow space in square feet?
16
16. What is the temperature and humidity in your grow space?
76f 40rh leaf temp 70 vpd 1.28
17. Have you noticed any insect activity in your grow space?
No
18. How much experience do you have growing?
Not much This is my 3rd grow

whatever this is it seems to be spreading. It’s taking over leaves that we’re healthy 2 days ago.

leaves turns dry and crispy/ crunchy

I don’t think it’s an insect. I put a couple of fan leaves under the scope and didn’t see anything.
let me know what your thoughts