this is the weakest light i can get ,now my new seedlins have been in a propagator for 5 days now and are doing well ,i was thinking about repoting them around day 14 (18-6)and putting under a 400w hps light with a good fan too keep the heat down ,will this be ok and if so how far away should i have the 400w hps light??
They are going to stretch some seeing that you are using a HPS light, not a MH one. I've never tried it before but I know people have grown start to finish with only HPS lights and had no problems. I'd say go for it, and because they are only seedlings I would keep them at a distance where you can feel no heat, they are still very young.
