For 6 weeks in veg you should have plants 3 to 4 times this size . The plants look good and healthy but at the same time under developed. When you water are you waiting till the pots are dry and light weight ? For few you might be over driving the plants I would try dropping the light to 50% for a few days . As for growing organic have you re fertilized your soil ? That soil will not last the whole grow . Gia green has some good products 2-8-4 and 4-4-4 and worm castings . Here is another tip over watering your plants will stunt them , it will also keep the roots from searching out for moisture . Let the soil dry out between watering. And as the plant starts to get bigger water the same amount but grow the circle . I sm going to put you onto this grower . Just watch this guy lots of really good info . https://youtu.be/xmlqU7KNqjE
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