Stunted seedlings

Your pots are quite small and the soil you are using has a lot of perlite in it, which is good for drainage, but has no nutritional value. Also remove the lid, cannabis does not need humid conditions, leaving the lid on will create too much artificial humidity and will only invite fungus and mould, plus your plants need to be able to breathe properly. The fact that the plastic lid will not let 100% of the light through plus being sheltered from air movement has resulted in your babies "stretching" a bit. Transplant them into bigger pots with good potting soil with less perlite and they should take off pretty quickly. You can also plant them a bit deeper than they are now, say 50% of their current stems under the soil surface. This will provide a bit more support for them, and in time, roots should sprout from the buried stems. Hope this helps.... Organoman.