Super Urgent, first time grower, batch might go to heaven - plants look beaten up, I suspect light stress or overwatering

I'm saying: too high VPD combined with windburn. → "Taco" edges, yellow-brown leaf margins. Could also be light stress. You also have a disturbed K/Ca uptake (marginal necrosis). - Keep fans away from the plants, let them blow indirectly against the tent wall (best oscillating). - Raise RF: target 55–65% before the flip - I know you mentioned your means are modest. If you can't get the RH up, the temperature needs to go down! - Tone down the light: HPS to 80–90 cm or dim by 15–20% for 3–4 days; then slowly back to 60–70 cm. - Water "clean" once until 10–20% runoff: pH 6.3–6.6, EC 1.1–1.3 mS. With soft water, add 0.2–0.3 mS Cal-Mag beforehand. - Keep at 24–26 °C. Flip only when new leaves come in smooth without curled edges (usually 3–5 days). Good Luck 👽