Hi
@Kreewl always put the maximum power, the more lumens your plant receives the more it will grow and strengthen. In the vegetative phase of growth they do not need the light so close, and the higher the light, the more your plants will stretch the search for the light source to place at 100cm is more than good. 400w.led.its more than good.I don't think that's why they are not growing. good luck mate 👍