How many Cfls = 5000lumen?

[headshake]

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

[nomadinexile]

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

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

[kushlvr]

I have 5 100 watt cfls in a 2'x2' space with 4 plants. Right now they are vegging. I just set up everything a month ago. I don't know how many lumens each cfl has, but it seems to be working. I'm going to see what happens in another month, hopefully by then I will be able to send some pictures. This is my first time growing under any kind of lights. Can't wait to see what turns out.

[smokero]

I have 5 100 watt cfls in a 2'x2' space with 4 plants. Right now they are vegging. I just set up everything a month ago. I don't know how many lumens each cfl has, but it seems to be working. I'm going to see what happens in another month, hopefully by then I will be able to send some pictures. This is my first time growing under any kind of lights. Can't wait to see what turns out.

I use 2- 26 watt 6500k per plant for veg and 1- 65 watt cfl plus a 42 watter both 2700k for flowering 1 plant and works great.Just for personal stash.Usually gets me a half oz that last me till next grow.

[neceros]

Lumens are pointless. Just stick to wattage as a guide.