The little girls!!

I'm not entirely sure if this is the answer but it could be part of it. A seedling of that age doesn't need nutes at all. She's perfectly content sitting in a neutral base with her dropped seed husk and attached cotyledons to feed off of. Once she's stable and has developed 2 or 3 new nodes, more powerful nutrition can be added to her soil, water, or both depending on what you're growing and how you're going about doing it.