Seedling stunted growth

So it shouldn't be me messing with the lights right? I'm at an average 18-20 inch height with 50% brightness on my ViparSpectra P600. The recommended height and brightness on the website are 20-24 inches and 60% so it's not light burn, right?

It’s probably just as organoman says. Some just don’t make it past sprouting.. or are severely stunted naturally. It seems you have other pots in the pic. If they all are looking good, then this is likely the case.

Unfortunately, not all seeds make it and this may just be one of them. It is always a good idea to plant more seeds than you need, for precisely when this happens and that way you are not wasting time and resources on something that will never be. It also allows you to only choose the best performing seedlings to continue with.

The yellowing one is starving or been over watered. Some course perlite like 30 percent at least in your soil will help out wonders. Roots need a wet then dry time. Plus the air the perlite holds. Possibly try rotating sides as you water. They don't need soaked at this stage in soil as well. Would be my recommendations, and advice. Good luck and hope you get it figured out. 🤜🤛

I haven't used any nutrients so far. I was messing with the light settings in the beginning week and second (height, brightness). And I don't think I have overwatered it.