I've noticed that my stalk has stopped growin...

Hi there ! You're scrogging on autoflowers strains , so I don't really think that you've done it to soon beceaus autos have a short life cycle it is better to start the sooner as possible ! Maybe you should consider a bit of defoliation to let the lower stems receiving more light or you could cut them off to help the uppers stems to grow biggers ! Concerning those little brown spots on your leaves you should check you PH , the better ph range is between 6.0 & 6.5 in soil ! I hope it will help you to make a killer grow ! 😁👍

Agreed about the pot size and the lights. If you could up to a 5 gallon it's not excessively big in terms of taking up space, and if you could up the light power I'm sure they'd like it. With watering, you could water less at one time, or at least ensure they are getting some drying time between being watered. You could remove the 1st screen in leu of a net and then use the screen for the 2nd layer? Happy growing,

i see you're using a 2 gallon pot with very little lighting, based on my interenet research, and bear in mind i have no experience in this, the height of your plants is very much within the parameter of what you can expect for an auto from fast buds and green crack in particular with such a set up. She stopped growing, so either do nothing and see, or input something to induce flowering and see. She's healthy bro, even with a couple of spots. What I understand is : larger pot larger roots larger plant, more light more energy larger plant. You're on the low side of the two main size things which is fine. See my grows for a size experiment. :-)

I agree with Michka when referring to the volume of water. If you’re using a highly organic mix you should use less water to your plants. Basically no run off, every few waterings little run off. Fungus gnats are a pain. Only way to stop it is prevent it first. Use a 1-2” layer of sand on the bottom and top of your pot. Sand acts like a wall for the gnats they can of penetrate it. Once you kill the larvae that’s it problem over. I wouldn’t be waiting for the mosquito bits, straight 10%H2O2 kill them instantly, prevents any rot from setting in from the gnats eating your roots...

My solution for gnats is another one, because neem oil only fits for plant eating insects. see here the picture . https://www.google.com/search?q=gelbtafel&client=firefox-b&source=lnms&tbm=isch&sa=X&ved=0ahUKEwipmf-Ki63cAhXG3CwKHcHNCmsQ_AUICygC&biw=1920&bih=953#imgrc=hRh5QPtMcEt2XM: its plastic cards with glue on it. the gnats fly on it and stick on the card. you can get it in a garden center.,And i wont use 2 liters of water for a 10 l pot...... it always depends on how hot it is in your indoor room. as u write its only 24 degree. Your plants will drown in 2 liters of water. you got to test it begin with 500 ml and look how she does. less is more. if your plant gets lesswater she shows you. if she gets to much she dies. If you have the feeling the soil is too wt and the roots are effected feel free to transplant her and give her dryer soil. they dont like it to have wet "feet" the roots will rot. i whish you a happy growing

For watering, you should use 20% of the pot.. If it is a 10l pot, use 2l of water... That's the best way.. Then, always wait that your soil gets dry before giving water again ! You should also have a look closer on and under your leaves to see if you can find any bugs, pest, flies or something.. If there is, use neem oil by spray on your plants, bugs and insects will get away... Hope i helped you my friend, don't stress they are looking good !