Checked on the seedlings today and I noticed that the 3 Purple Kush are stretching pretty good. They are out of the dirt about 2 1/2 inches with the first leaves just starting. I have my lights set at 18” and putting out about 12000 lux. Using 240w 3000k QB on a dimmer. Should I move the light closer? Or turn it up? I do have a vivosun 300w burple light that seems decent for seedings. Temp is at 21 degrees and humidity is sitting around 65-70%.