Funny, but I can tell you that I have 400wMH and 250wHPS I grow in a 3x5 space, but make sure that you leave spacing for plants to spread out a little...I ended up with such a great germination rate that I grew many more than I had planned and 2-3 are small vine wander around everywhere and way to short, but I'll smoke it!...I would say that you could grow 6 strong thriving plants with those lights...latewood...p.s. I have 14 growing with these lights right now! too many though!