Plant suddenly died


My plants suddenly died and I’m wondering what I did wrong. In the last forum they thought it could be over watering, but it was doing great for 2.5 weeks then they suddenly got sick. Someone said WPM (white powdery mildew). Don’t know much about that.

This is what they look like now

This is where they were 3 days ago

This is my set up

My ph currently

This is my soil.

These are my lights

I usually keep my lights on 18hours with 6hours off
I Water about 2tbs a day. Add a little more after I saw leaves wilting

How close was the light?

And does that white stuff wipe off? That is pretty strange

Can clearly see the WPM on the lower leaves in this pic.


This light is about 4”

These Led lights are about 2” or closer away!

That could be the problem
You can see the light in the picture of the set up