I have a 6ft x 4 x 6ft high grow room (it's actually 8ft wide but I want to partition 2ft off to try SOG). So far I have 2 x 250W CFLs (red spectrum) in reflectors. Now, I know this is nowhere near nough light to flower 8 x 4ft high plants so I need to buy some more lights. I went for CFL because a) they run cooler than HPS b) according to the makers blurb, they are more efficient as their light is 100% PAR, where as HPS waste alot of the power they use as heat and light the plants can't use (as I understand it). And with the way the cost of electricity is rising, I want to use whatever lights will give the best yield for lowest running costs.

Heat build up won't be a problem cos I intend to install a ventilation system.

I have read lots of threads on here concerning lighting, trying to decide whether to stick with the CFLs or go for HPS.

Can anyone please advise on this, and on how many lamps to get good results in this size space?

Also, I know I have read somewhere on one of the threads a formula for working out the size of fan needed, taking into account resistance caused by filters, ducting etc., but I can't find it now. Can anyone point me in the right direction?
mygarden Reviewed by mygarden on . Confused about lighting & info on fans PLEASE I have a 6ft x 4 x 6ft high grow room (it's actually 8ft wide but I want to partition 2ft off to try SOG). So far I have 2 x 250W CFLs (red spectrum) in reflectors. Now, I know this is nowhere near nough light to flower 8 x 4ft high plants so I need to buy some more lights. I went for CFL because a) they run cooler than HPS b) according to the makers blurb, they are more efficient as their light is 100% PAR, where as HPS waste alot of the power they use as heat and light the plants can't use Rating: 5