Quote Originally Posted by nomadinexile
That's one measurement of a much larger picture. Useful spectrum lumens received is really what you are concerned with. From Maijuana Horiticulture: The Indoor/Outdoor Medical growers bible, by Jorge Cervantes recommends 10,000 output lumens for a flowering plant. I have heard lower amounts used though. Also, different 23 watt bulbs have different lumen counts. Many variables

I would try using two 23 watts per square foot. 50 watts per square foot, while a very basic measurement, still works within the normally used lighting types like cfls and hids. But the more watts you can put it, and still keep it cool, the better off your plants will be.
i don't know why people use watts as a guideline for lighting in a grow room. watt has nothing to do with lighting specifically. watt is merely a measure of power consumed.

on top of that you give him a quote from a reputable source (jorge cervantes) of 10,000 lumens per/sq ft when flowering and then you interject with the 50 watts/sq ft comment.

if we are using 23W, ~1600 lumen bulbs that would give us well below the recommended 10,000 lumens/sq ft. it would in fact only get us ~3200 lumens, still below the MINIMUM recommended 5000 lumens/sq ft that most recommend.

i understand that lumen is not the best measure to use when making a decision pertaining to lighting, but is readily available on most packaging and an easier comparison than trying to get into watts. what if a bulb is more efficient than another, does the watt rule still apply? how does it apply to LEDs?


-shake