No nutesA deficiency in a plant that small is unlikely. What are you growing in? How often are you watering/how much? Temp, RH? There are many causes of yellowing leaf tips, in seedlings it’s often too much water. Are you feeding?
I ph my water to 6.3- 6.5 it'sTo my eyes it looks like the soil does have a little charge. It was a little too strong for a seedling so it burnt the first true leaves at the tips. But now that you're on to your next set of leaves, they look to be a little yellow and the plant wants more food than what the soil has to offer. I would do as advised water. Let the roots Chase and see what it does for another 5 days before I decided if it needed more nutrients or not. Are you pH adjusting the water you put into your soil?
OkayRide it out, start watering a little further out from the plant, you want to force the roots to follow the water. I’m not familiar with that soil, so I don’t know if it has any nutes in it.