Hi
@GrowThings! I have to disagree with our friends here, your plants look very dark and don't seem to suffer from a Nitrogen deficiency. What I see is yellowing between the veins, which is a symptom of a cal/mag deficiency. This deficiency often hits the bottom leaves at first, then spread to the upper ones if not solved. By the way, since you're growing in soil, you might need to transplant your babies to bigger containers in a few days, or you may encounter root-bound. Hope this will help, keep us up-to-date and happy growing 👊