Shook, from everything I've read so far, my first thought was that it might not be a light issue. Baby seedlings don't require much light; for that reason I would suggest that there is another reason for the slow growth. At the same time, to make sure ('cause it's hard to tell from here
) get those plants closer to the lights. Those lights are only effective for a short distance so put something under your containers or something to get them closer. At least then you'll be able to eliminate light as the problem if they still do not grow properly. (Incidentally, I see you were thinking that the light intensity might be causing slow growth - that's definitely not it, I can promise you.) Use plain water (no nutes) to water/flush them if you're not already as it sounds like this was an issue. I'm not sure I understand what you're using for soil, but if it's something decent and you keep flushing them with plain water and get the lights closer there is little else you can do. The good news is that, you're planting them outdoors so if you can squeek them through this they'll be fine.