From what I can tell, it looks like it’s mainly one plant with these issues. And it appears like it’s mostly on upper leaves. Which leads me to believe it’s mostly heat stress. The first 3 pics of plants don’t look bad, the 4th the leaves seem to be burning up. Is it exposed to heater or lights more than the others.
One plant was around 6-8” away from the light.
Correction, now adjusted to 10”
Mentioned was limited on room.
Heater was ground level directed near’ish, doesn’t sound like it was directly up against or super close to the pots from the conversations.
You would need a TDS meter to measure dissolved solids in water.
No, based on the appearance of your leaves you don’t have a deficiency going on. What type of soil are you using.
I’ve seen the average temp posted multiple times, but what are we looking at for highs and lows? If you’re swinging from 75 lights on to 64 lights off is no big deal. But if it’s more like 90 lights on and 50 lights off isn’t going to work out well. Growimg in a garage with your climate isn’t going to be a great expense without climate control.
Dbrn32 is right, that is too much swing. In fact, that’s pretty much what I’m facing also. It’s not ideal and some plants do better than others in this type of situations.
Here is a list of things to check:
1 Check VPD (dont go by charts shown in this topic unless your leaf temp is same or they are useless)
2 Check PH Meter (calibrate)
3 Do Soil Slurry (test nutrient levels)
4 Check Soil PH (can be done with slurry)
5 Check Soil For Excess Moisture
To me it looks like a combination of things…