I’m in aus mate we do degrees Celsius and the room temp has not been over 28 degrees but as this has been happening for over a week now lifted lights 6 days ago as they may have been to close as in light burn and real slow recovery some getting worse I recon I have 3 600w lights in a 3 metre by 1.5 m room have I got to much light? And have only realised over the last couple of days maybe getting to cold over night could this be the issue I will put more photos up of the other plants to compare
3 x 600 watt MH bulbs? The plants look fine to me except the curling, lights too close maybe? In photo #10 the (shorter) plant in the front looks fine. Can you turn the lamp ballasts down, maybe to 50% power for a few days to see what happens?