hello my seedlings popped up sunday and monday i have them under floro right now 24 hours what i want to know is when should i put them under my 400watt mh light on 18/6 thanks for any help.
as soon as possible just rember the first week or 2 the light needs to be backed off or it will burn the young seedlings
Two approaches -- you could leave them under fluoro for the first week or so, as long as they are getting enough light that way no problem. Or you could put them under the MH right away but as Ice said keep the light a good distance away, I would say at least 2 feet.
thats exactly how far they are away from the bulb everyone says that i can have it lower cuase its a hood with glass at the buttom and i have a 6" fan pulling the heat out the hood and out the room. my humidity is on the low side between 58-60% with the 400 watt light with the floro it was at like 80% is it ok for humidity to be low as they are seedlings and in vegitative i know in flowering i want it low just not sure about veg thanks to those who replied
Although heat is an issue, it is not the only concern with new sprouts. I had a new sprout under a 250 HPS and it started turning a light yellow. The light is just too intense for it at that age and it starts light bleaching. I simply moved the plant to the outside of the footprint so it wasn't getting as much light as before and it worked. I would keep the MH a good distance away as they say.