If you're using that 4' square footprint, allow 4 feet between each light so that the light is centered over that group of plants.
If you're flowering directly from new rooted clones, I highly recommend setting up the lights so that you may raise them a little bit for the first week while the plants acclimate to their new situation.
I like the Y duct plan. Sounds good. You're going to want a KILLAH blower to handle that; a 6" high output blower is probably the minimum you'll want for all that light. If you do a sealed room however, things are a little different. I don't know the first thing about those! Although a sealed SYSTEM where your veg and flower rooms are connected and recirculate, with CO2 addition and a cooling system (like a window AC) in the veg area, or 'lung room', is fairly simple to set up.
stinkyattic Reviewed by stinkyattic on . What could my problem be? My yield has sucked! Like only 400g for 1600w of light. I am using pro-mix soil w/ fox farm nute program. I water eod w/ nutes (liquid karma and cal-mag added when needed). Donors are ppp, ww, nl/bb, HK, AK-47. The plants have been falling over and I try to stake up most of them. Could the 4 weeks in veg have a lot to do with yield? I only use fluro's and the mom's are under the same. They are kind of far from the plants when they are small. I do not have a dehumidifer and I use city water Rating: 5