How fun! I'm currently running Blue Dream in organic supersoil in cloth pots...it's my second run like that. My avatar is actually my current Blue Dream grow that will be harvested within the next week or two.
You mentioned that you have used that soil several times. Do you mean that brand or that actual soil? One of the huge benefits of supersoil is that you can use it time and again without any loss in performance. However, if you're using the same soil over again, you have to add amendments back to it and let it cook for a couple few weeks to replenish the nutrients that were removed and to get that soil biome going again.
Question: Did you do this if you're re-using soil? If not, that may be why the girl is a little pale. If you did, then it wouldn't hurt to do a gentle tea. Something well-balanced and designed for the vegetative stage. I use Earth Dust, but there are several that get good reviews. If you do a tea, do it like half-strength so you don't burn them.
Also, like you, I go from germinating the seeds to putting them in a rapid rooter until they develop their first real leaves, then I go directly into a 7-gallon cloth pot. Nothing wrong with this, but it does require some attention to watering. It looks like you're doing a good job of doing just a little water around the base of the plant so you're sure the little roots get plenty of oxygen. However, if you're not already, make sure to occasionally do a light watering around the rest of the soil, maybe a day or two after you watered around the base. This helps to make sure that the beneficial microbes are staying alive and ready to take care of your plant as soon as the roots reach out into that section of the soil. I made that mistake once and since where the roots were growing out into wasn't moist and the biome wasn't chugging along, I had similar symptoms as you. Well, not me, but my plant
Since I'm assuming you're doing an organic grow, I suggest that you stay away from things like synthetic supplements. These often kill the fungi and bacteria that organic grows depend on since that's what makes the nutrients available for your plant to uptake. I will say that Blue Dream loves Nitrogen during the veg stage! I usually add extra to mine in the form of urine at a 10:1 ratio every 10-days or so in veg. If you take medication though, you may want to opt for guano, fish meal or bone meal since some medications are excreted in urine and you probably don't want your plants absorbing that.
Regarding the lights, I've never used those, but my guess is they come with a chart showing how far away they should be at different intensities at different stages of growth. If those bad boys are up at 100%, you'll probably need to keep them pretty far away from the plants. And even then, it might be too much light for the young plants to process. Check to see if Flora Gear has any suggestions along those lines. Off the top of my head, 400w up at 100% seems like too much intensity.
With organic growing, usually less is more. Make sure that temps, humidity, ventilation, and circulation are all under control and you've got 90% of your problems stopped before they start. The other 10% can be avoided or managed by making sure that you're taking good care of the soil and the biome in it - correct watering techniques and adding amendments/teas judiciously and purposefully.
Have fun and keep us updated!