Slow Growing?

Thanks for advices fellas. I use 400W MH for lighting. Once I had issues with overwatering and since that, I avoid overwatering in my own way... I guess this is the problem. Now I water them generously with nutrients and let them flow. Thanks again. Peace!

Seems like a slight lighting problem, the plants are stretching and struggling to find light they need to develop! First try repotting them in a bigger pot covering the stem leaving about an inch/2.5cm of it above ground, then move the lamps as close as the heat lets you, if that's not enough do what you can to increase the light output (try adding a LED flood light - cheap and efficient for a short time). Don't forget to water them with nutrient rich solution! at this point they need those minerals to develop! Hope this helps! Good luck and happy growing :)

They are VERY small. about the size of a 10 day old one. The only thing you didnt mention and what I would guess would be a lighting issue. It is in soil so doubt it is nutrient related. This is to drastic for that. I would say poor lighting is the issue here unless your PH is higher then stated, then that would be an issue.

They are looking yellow, probably need nutrients. Also seedlings prefer warmth around 80 degrees and humidity around 60%. Are they sitting on the cold ground? Try putting a towel or some sort of thick cloth between the floor and whatever you have your plants sitting in. In the pics the dirt seems very dry. I would water the whole thing with some nutrients. Then just let it dry out, might take over a week but it'll get the water it desperately wants.

They could do with more/lowering the light. The stretch is the plant looking to get a top up. I water when I pick up the pot and it weighs roughly 75-80% less than when it had just been watered.