Been my experience that seedlings need a week or so to be able to stand the full 400 watts at the correct level.... Just my humble opinion, no offense meant. :farm: I know the strain and pheno type of what I'm growing and I'm able to start them from seed using my MH 400 watt, but this strain is Bred for indoor and it loves the light. Every other strain I have grown I have had to run them under floro's for the first two weeks of veg. Since I don't know what strain and pheno your growing I am just guessing at the right advice. hopefully it will be helpful...I'm still learning and I have over 20 years under my belt.just have seedlings, how low should I go?