I use a large oversized PC fan for active intake, and a passive intake next to it. Active intake isn't as important as active exhaust, which is kinda a necessity in a closed environment. Exhaust should go ideally at the opposite side of the intake. Intake low, exhaust high.
Yard/lawn soil from gardening shops often isn't very suitable for mj plants, especially small ones.
Not sure why you are not getting more replies... maybe a picture of the updated situation can attract some more repliers. And have you changed anything since the previous picture?
Silly question but what is the kelvin rating of your CFL's.I am only taking a stab and offering opinion because I am not an expert,but when I first started mine were lime green like that and noticed my MH was 4200k two days after I switched to 7500k they looked great.Again don't take this as your problem,just something to check.
coco coir requires cal mag every feeding. there may be enough in your tap water but to be sure get some and add it in progressive amounts, starting at 1ml/gal and progressing to 5ml/gal. also coco has no nutes in it so tap water may let it grow a little but when it starts to foliate gradually bring nutes in at 1/4 dose or 1/8 dose. every week give it fresh water and get it to runoff to leech salts off the roots. to avoid salt buildup don't allow it to get too dry and also remember not to over-water, this will cause moisture stress.