Yellowing of leaves

[Bubblesmc84]

Hi,

I am currently part way through my first grow and I have noticed a couple of leaves have started to go yellow around the edges.
I am growing a northern lights autoflower in coco, I ph my water every feed, every second feed is with nutrients. I am using cfls as a light source as the grow box is my attic and i didnt want to generate too much heat.
Can anyone offer any advice on wether this is something to be worried about?
Appreciate the help.

 

[ellz]

Looks to me like nutrient burn.
https://www.growweedeasy.com/cannabi.../nutrient-burn

 

[vostok]

slight approaching nute burn, with a good need for some calmag(see the yellow centrel vein)

miss a few nute feeds IMO or just pot up

in truth attics are not the best place to grow weed, as temps swing too much
ensure your cfls have a large chunk 50/50 warm white(2700k) going to full warm white come flower
for correct vertical growth

if you want small plant simply trim the roots Bonsai style every 2-3 weeks

good luck

 

[SoOrbudgal]

Nothing to worry about we all do nute burns when we learn. Have you seen any preflower, it will get lighter green/yellow at bud site when it does. Good luck