I'm thinking that you are going to experience heat problems when you close up to go 12/12.

You said you have a 400+ cfm fan pulling through the light and reflector to exhaust. Remember that CFMs drop off badly when pulling through filters, ducting bends and long runs. Are you pulling through the filter? If not, pushing through a filter is very inefficient and cuts your CFMs even more. What about your intake? Where is it and how large? Is your intake lightproof?

You've got to be able to pull fresh air into the grow area as MJ loves fresh air. And it will help keep your temps down, which in turn will help you keep your problems to a minimum.

Edit: I would consider adding an additional exhaust fan just for ventilation. You should also investigate isolating your light from your grow. In that case, you would have an exhaust fan pulling air from outside, through the light and out that exhaust outlet. Since this hot air never touches your plants, it should not be stinky, so you don't have to filter it. Move your filter to the pull side of the new exhaust fan, which will scrub the stinky air before exhausting.
crabbyback Reviewed by crabbyback on . Any advice/potential problems? I am on day 14 of origional potting and having some fun with some good bagseed. But am getting concered that I have no greenthumb. So anything that you might be able to tell me differently I would appreciate it. What is your experience level? (first timer Your Equipment: Rating: 5