I haven't used my brain in a while and it's a little dusty. You are correct. I will be more aware before I post in the future! Thanks.

Btw, I just got a "bright" white 23w for my inverts that is 1500 lumens. So using a baseline of 5000 desired output lumens, you would need 4 per square foot. (actually 6000)(of this brand and spectrum) IF you have everything else dialed in, and can cool 7/sq ft., you get 10500 lumens.

That's a lot of cooling. You would be better off imo going closer to 4 until you see you can keep temps in check. (relative to your experience, knowledge and equipment) Hypothetically you could run a space heater in there too and keep it cool, but most people won't pull that off!

Sorry again about the mistake, I will be more careful going forward. Peace



Quote Originally Posted by headshake
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