3 days after germination, I realized that the plants were light deficient, so I turned on the main grow light (Vivosun VS4000) @ 50%, 20" away from the plants. This fixed the issue, and the plants exhibited steady growth, with the stem becoming slightly thicker every day.
I have been watering these plants with 6.5 Ph balanced tap water, with a tiny amount of hydrogen peroxide. Prior to watering the plants, I let the water sit for at least 24 hours to let the chlorine evaporate.
The Pineapple Express seedling is by far the most successful one, looking the healthiest and growing faster than the others.
The Ethos Cookies #16 plant experienced stunted growth during the last few days. However, it seems as thought it is picking up again slowly. I also noticed that she has a deeper green leaf color than the rest of the gang.