yellow cotyledon

Hello, this is my first grow, I bought 2 auto flower seeds online from herbies seeds USA, I I bought 1 do-si-do auto, and one blue berry auto. I have an air-cooled 1000 watt hps hooked up to a fan for ventilation When I started this grow my buddy had some plants that had gotten basically forgot...

I have 3 plants, all are about a week old and I made the mistake a couple days in by overwatering...this is my first grow, but anyways I stunted the growth for a couple days as I also let them dry out. I began to notice the Cotyledons began to die but earlier than usual. I read that all the...

This seems like a tough one. I have 3 plants that I'm treating all mostly the same. My Northern Lights, which so far has been the most sturdy of the bunch, thriving through all of my mistakes, is currently struggling a bit. 11 days ago I fimmed both the Northern lights and the Jack 47 (back left...