Indoor Northern Lights looking frail

[Rufus.Gray]

Problem: browning leaves, edges of leaves curling up, dropping leaves

Medium/grow method: 3’x3’ tent, Coco Loco, 2 gal pot, 24/7 light at 16”

Feed: and supplements used: Greenleaf Nutrients Sweet Candy and Mega Crop

water source: store bought spring water, non-ph

Strain/age: Northern Lights, week 5-6

light used: AutoCob 3500k x 3 (directly under 1 at 16 inch height, while the other 2 are about 5 inches lower.

Climate: 80F/60rh

Additional info: Seedsman freebie that I fimmed at the 4th node. After that, I tied down branches until I ran out of space on the pot, then I just super cropped the main stem. As much as I’ve abused it, it just hit a 6 inch growth spurt in early flower, but now it looks kind of sickly.

 

[Waira]

-- lights are too close, those up-curled edges are tell-tale for too much light,..it stresses the plant and kicks off other symptoms...
... get that up to 22" or so, and go down to 20/4... After a lot of input from here and around other grows, it's clear to me at least that 24/0 is of no real benefit, no significant yield improvement vs. 20/4... The plant can only use so much light energy at a time, daily (read up on maximum daylight integral), and past that it's actually a detriment. There's a couple good threads on this in the Myth Busters sections too,...

 

[BII]

-- lights are too close, those up-curled edges are tell-tale for too much light,..it stresses the plant and kicks off other symptoms...
... get that up to 22" or so, and go down to 20/4... After a lot of input from here and around other grows, it's clear to me at least that 24/0 is of no real benefit, no significant yield improvement vs. 20/4... The plant can only use so much light energy at a time, daily (read up on maximum daylight integral), and past that it's actually a detriment. There's a couple good threads on this in the Myth Busters sections too,...

To what extent is full darkness, no light at all, required during the plant's photosynthesis downtime, while the tent lights are off? For example, if the tent is open and exposed to general room light, does that count as off/downtime?