slow growth, 7th week from seed (pics)

I hoped that I wouldn't be back in the plant problems section again, but here I am.

My 12 plants are all about 7 weeks from seed, except one, its about 3 and they seem to not be growing much, after 3 weeks I used a tiny bit of nutrients, but someone told me that it was too soon and I needed to wait until they got larger.

It's been 24 days since the first nutrient application So I have applied them again, Hoping that they can take them this time. However I applied them only in minute amounts to be on the safe side.

Also about 3 weeks ago I installed a 150w MH bulb that boosted the plants alot at first. Their leaves stopped being droppy and curling

I have pictures that maybe can help you diagnose what I am doing incorrectly

I would figure that by seven weeks they should have been much larger than this

What type of soil are you using? Also, how far away is your light from the plants? I have a grow @ 3 weeks with stunted growth. Clumsy me followed directions on the box and my light was 4 feet away! DOH!

After moving the light (430W HPS Son Agro) 24" away my ladies perked right up and are growing fast as ever. Hope this helps, but we need more info to see where the problem is.

Peace

I'm new, but 7th week, i would start to think about ROOTS. I sprouted my seedlings and in a week transplanted. They had roots goin out the side of the jiffy pot by 3". Like i said, i am new, but i have run into this problem already. Anyways good luck.

They probably are root bound, those cups are letting light into the roots and they look over watered. Im no expert though.

7weeks???!! thats insane, definately bring the light closer, transplant to a bigger pot, and they look like they are over or underwatered ( they look droopy ),, Good luck

Looks like a ph/overwatering problem. They could be root bound depending on the strain. but ive never had a problem with root bound in party cups. Try to let the soil dry. then water with ph'd water.

I'm a week into mine and and seeing similar issues, mine have lights close to plants, any ideas from looking at the pics?

Grow room specs:
3-27watt cfls (5500lumens @5000K)
Temp swings between 70-95F
Humidity 45-65%
Ventilation decent but certainly not ideal
PH unknown (picking up meter tomorow) been watering with purified water from store

Plants are 7 days since breaking through soil.
4in. Pot for the one and 16.9oz bottle cut in half for the other (i know not a good idea, i'm starting some new seedlings with peat pots, and using top soil from Home Depot this time, seems pretty neutral without any added ferts)

I'm also limited on space and amount of electricity I can use, was planning on going 12/12 when plants hit 4-6in to keep under 2ft. (this is just bagseed by the way) can I get away with 1-1.5gal pots max?

Thanks for the help!

Jack your little plant is fine. Dont rush it. you can get away with using those pots but with 3 cfls your yield will be minute.

ok, just got worried since the day before they were nice and perky and now drooping a lil with some wavey leaves. I'll prob throw in one more 23 watt and a 14w but they are 2700k and 3500k so i dont know if that would even help, when it comes flowering time i'll up it to 200watts (13,000 lumens) of 2700k.
appreciate for the info!