3x3x6

Northern lights auto before feeding tonight

hello everybody, here is my og kush fem from dinafem, its 1 month old and the new leaves are getting yellow, they are under a 400w mh bulb in a 3'x3'x6' tent, any help or advice would be nice, thanks!

Howdy guys! I'd love your input on the completion of my grow tent. This is my first indoor grow- I grew outdoor when I was a kid- but this is my first indoor. (can legally now grow up to 12 plants) Currenty 3 Northern Lights Seedlings 5 days (was given the seeds for free by a friend) First...

Can someone please tell me a good soil to use for my 4 plants in a 3x3x6 grow tent 900 led light. I'm located in southern Ontario canada