Need your always inspiring advice

Hey guys i was wondering if you can help me. Im not sure but i think theres something wrong with my plants. i have 9 of them growing in with a 600w mh bulb with a 20/4 lighting. they have been going on 3 weeks and are still pretty damn small. the pics are included...im using miracle grow...should i change the soil???? im watering about every 2-3 days. I did have some problems with the temperature but it has been between 70-90 degrees and the humidity in the room did drop due to the dry cold front that hit but i got a humidifier and placed it in the room a few days ago and it has kept it at 40-50% and holding steady. They just dont seem to be groing up as fast as i thought they would during this time. Any help is greatly apriciated

Did you start from a seed or clone ? I think A seedling heat mat will be beneficial for stimulating the roots will help it grow along nicely,I have 2 of them for my babies that run 24/7 until they get strong enough to not need it.I think a majority of the folks here will agree that anything Miracle grow is a No No....Some guys may like it... But Ive experienced that Fox Farms Ocean Forest or Happy Frog Is the Best Bet for soil,grow the little one until its ready for transplant and surely change soil and don't tuck it into their new soil too tight.Try to keep temps at around 75-80F if possible.

I started from seed...3 weeks ago from when i originally planted them in a germination kit that gave them the start but since then have transported them into these pots they are in now. they have been in the new pots for about 2 weeks and have grown some. do you recommend me trying to replant them into some foxfarm?

do u see any sort of deficiency? how big should they be at 3 weeks from germination to current?

I dont see any deficiency but the Miracle Grow thing LOL But when you grow from a seed it takes awhile for them to get going as if you had done it from propagation. I would wait until they outgrow the cups they are in to transplant,doing it now would create unneeded stress for them.At the current time they seem to be doing well from germination time to how big they are,I would be patient and let them grow out of their current homes and put them in some Fox Farm Ocean Forest.I would also be sure to watch the lighting temps and make sure they dont get over heated and get a seedling heat mat for sure ($24) Stimulating the root growth will help them immensely,The heat mat will take the ambient air temp and escalate it 20 degrees F to the roots and it really does wonders for babies.