Brown spots, curly leaves

Hello,

This is my first DWC grow. The plant is 20 days old. The PPM is a cosntant 1050, PH is a steady 5.8-5.9 for the last 5 days. But in the last 3 days, after I started misting the plant it started to curl, some upper leaves get wrinkles, the edges of the leaves started to lift and the spots apeared 3 days ago and turned brown and started to spread. I am not sure why this happens. I use Advanced Nutrients M-G-B 1 ml per liter, voodoo juice and B 52, 1 ml cal and 1 ml mg per liter of water. This looks like PH and Potassium problems but I used only 1/4 the dosage. I have a very small fan. Non oscilating. Temps are 20-21 with 55% humidity

What do you think. Is the PPM too high? Should I hold the calcium and mg fert? I don't know exactly what to do

HMMM...If this wee my grow...I would wait a while longer so I could see if the issue continues or worsens. Right now I see nothing that could cause irreparable damage.

I understand. The thing is, the spots seem to spread very fast Could it be too much Ca? On the calcium and magnesium botles they say 1 ml per liter. I used about half. Could it be it is too much for a 20 days old plant?

The led panned (bonsai hero 85W) is about 15 cm away

Well the rusting continues I added 2,5 ca and 2.5 ml Mg in the water and I put some more distance between the pannel and the plant.
As you can see the spots are now visible on the first set of 3 leaves and started to show on the 3rd node leaves
I fimmed it. She kind of stopped drinking so much water as the previous days but she is still growing a bit. I will wait and see as I don't know what the problem could be. Ca def, led to close or something else...

seems 1ml cal plus 1ml mag per liter is quite strong; what u been spraying with?

Hello, no, I mean in the bucket. I grow DWC. I used 7.5 ml for 14 liters of water.