My daily inspection turned this up on my larger black widow.
It could just be light burn. I had the lights around 12" away, but a little growth spurt moved the plants to about 10". It’s only the upper most leaves. So I moved the lights up to 14". It’s also been over a month in this soil so I decided to brew up my first batch of nutes for the girls. Very mellow with just 5ml catalyst, 5/ml grow, 5ml micro, 7.5ml cal-n-mag /gallon. If it’s not light burn but a mag def, or potassium def this should help.
pH is acceptable ranging from 6.4-6.6
Ppms of runoff are a bit high. In was 650 out ranged from 985-1320. I’m guessing my soil amendments are responsible for that.