Seedling going yellow

Hi there, I would say it's simpler than overwatering or nute deficiency. Every good thing must come to an end xD. Since that's an autoflower I would say she's reaching the end. At some point the plant will stop taking nitrogen as well as other nutes and the "system" will shut down. 14 weeks seems like it's about it. With autos it's all about timing. If we miss a feed or make any other stress she won't reach full form by the end of the cycle. Check what the breeder says: "indoors it grows into a small to medium-sized plant enjoying 18 hours of light per 24 and finishing its life-cycle in 55 - 60 days"

What kushgang said coco has no nutrients so if you didn’t build a soil with coco meaning adding worm castings and dry admendments etc .. and your feeding using bottled nutrients your going to have to feed her you might need to add some calmag to the feeding happy growing

a bit of overwatering and nutrient deficiency...

Hello happygrass yes you need to give nutrients because you are in coco. In coco there is no nutrients in it so you have to feed since the beginning compare to soil which contains nutrients. Good luck. Bye

Maybe a little overwatered or ph slightly out of range