Anyone know why top leaves curled down like this? ...

Hi @Leeguan! What you're having here is a Nitrogen Toxicity, also called "the claw" because top leaves usually look like a bird's claw (curling downward). This can happen because of too much Nitrogen in the feeding solution - of course, but this can also happen if the plant doesn't get enough light to "transform" the nutrients into energy. Now as a solution, I'd recommend to stop nutrients now and until harvest. Nitrogen toxicity is known to give a very bad taste to the buds, so it's important to start flushing as soon as you can. If you can give this baby more light and less nutrients, while controlling the day&night temperatures, she should be fine. Hope this will help, keep us up-to-date and happy growing 👊

Im going with heat stress or light stress from the 600 led, they can be unpredictable. Possibly check your distances and place hand at plant level to see if it gets too hot in 10-15 seconds. Also like mentioned you want all fans creating a gentle breeze around the plants, try not having then directly at the plant if the are, bounce air off walls etc because wind burn can warp leaves bad. With the nutrients and it being an auto, ive heard some of them even need lower than 1/2 strength. Just mess around with a few of everyones tips and see what makes a difference. Happy growing 🙂

Hi Leeguan, i see small darkgreen droopy leaves, and its just the top leaves=?In the first picture you can see the Reason . look at the left side of the pic there is a fat ventilator that blows directly onto those curled leaves........ its wa windburn.... and i see an incoming nitrogen excess the leaves are dargreen and the tips seem to be burnt In the comments i leave you 2 links , one for windburn , one for nitrogen excess.. happy growing move that thing away and she rcovers soon

Hey man i don't know when you took these pics during your light cycle, but plants kinda go to sleep sometimes and that's what i can look like. Otherwise check out how often you're watering, or the heat if it's kinda hot 78/79F it can make your leaves droop down and keep your stalks kinda slim. Make sure you got enough space for the plant to stretch i'll follow along ! good luck !