Start with the links in the green bar above, like "growing basics", then move to "plant problems" and read (then start new seed).
Its way to late to try to save these, they are done. They should have been bigger than this at 3 weeks old, even if they were to only get 18" tall and finish in 60 days. My autos (wet teddy bears) at 100 days are 6 feet tall.
What is that they are setting in?
What is the PH of it?
What is/was the temps and RH?
600 watt rated or actual pull from the wall?
What have they been feed at what PH?
How often are they watered at what PH?
What is was the timing of the lights? And distance?
How long were they to take from seed to harvest per breeder?
Anything and everything else!