Kinda looks like PH burn.
Et them flushed . if not start again. Try photos and coco as your medium. This isbfor next time. Give them water phd for now and check run off phvand ppm. Did the other bits of advice help. Where are they at now
This is my Mexican airlines auto in 6vgallon under phlizon 150w cost 120 pound over here. Consider a smaller growing area unless under a boxed off area but id get maybe a combo kit with light and tent
What are you using for air distribution
when we talk of fans you need some traditional fans to blow the air around. Then you have for eg a 4x4 tent a 4vor 5 inch fan bringing cooler air and an inch bigger for negative pressure taking hot air out
This is what you would attach yourself for odour control.
I only have a soil PH tester and it tests at 7, these plants were in a spare bathroom with a floor fan. how do I go about flushing them out?
I do that to mine periodically. In my case it’s fertilizer burn. I clip the yellowing leaves.