Leaves yellow & curl in 2 autoflower cycles. Day 25–27°C / night 21–22°C, RH 50–58%, VPD ~1.2–1.7. 60×60×180 box, pots 6.5/6.5/5/3.2 L. Lights: SF1000 (70–80% dim) + SF1000D (fixed), 16h; 34–37k lux top, 28–29k side. BioBizz ~50–60%, pH OK. Light stress or root/EC issue?