Vanilla Kush

Hello there. Same thing with my Northern lights. Like clockwork they would start to droop out at hour 19 on a 20/4 cycle. Mine was due to relentless light/heat stress from my lamp and I would presume that's what we're looking at here, as well. I wouldn't change the time as 18/6 is a good cycle. I would recommend moving your lamp up 1-2 inches a day, until you notice these symptoms tapper off. They're just a tad stressed out after a long day. I also see your RH is kicking around 40% and Heat in the day is hovering around 27 degrees. Not bad numbers, but I would suggest balancing out your humidity to heat ratio a bit. Try moving your RH up to 50%+ RH and drop your temperatures by 1-3 degrees, for day time temps. This should also alleviate the stress you're seeing. Need any tips on creating humidity or mitigating heat and/or humidity, drop me a line in PM👌 *I always ask that you wait for another opinion from another site member to verify my response!* Cheers and good luck this week👍