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How many watts for 3x3 flower?ligh
- Thread starter COS
- Start date
IMO the "optimum" would be to have available around 450W(or more) of latest leds, and dimming them on 300W.
One qb240 would also be ok but canopy management would be even more important. I use two qb240 dimmed at 70% and sometimes it's too much for the nearest tops.
Cheers
One qb240 would also be ok but canopy management would be even more important. I use two qb240 dimmed at 70% and sometimes it's too much for the nearest tops.
Cheers
Switcher56
Comfortably numb!
600W, that is what I was running in mine, 300W in veg tent.
Are you sure it's 3x3, as 1x1 is 20% bigger.
cmh is about 2 umol/w and KB about 2.6 umol/w so you may need the full 480w
I imagine you will be fine with about 300w. Lot's of people use less light and do better. Prime example is people that found a 315 better than a 600 sodium. You might just trip over yourself if you run 480 straight off the blocks. LED's can take some feed adjustments before you ramp it up
cmh is about 2 umol/w and KB about 2.6 umol/w so you may need the full 480w
I imagine you will be fine with about 300w. Lot's of people use less light and do better. Prime example is people that found a 315 better than a 600 sodium. You might just trip over yourself if you run 480 straight off the blocks. LED's can take some feed adjustments before you ramp it up
Mars Hydro TSW 2000 is perfect for a 3x3 dimmed to 75%
I've already bought the king bright 480 watt QBs. I just hope I didn't mess up going with leds, have always used hps/cmh, but will be a welcomed change if it saves on my electric bill.
Without knowing how your lux meter responds to LEDs, it's impossible to say. The same light, or three different meters, will give 3 different results. Results that can easily be 100% different.
Perhaps if we knew what meter you have, we might be able to tell you how inaccurate it is. Price has no bearing on this. They are simply all different
I'm sure you will be happy. I was a staunch hps guy and now I am LED, seeing far greater results.
The most common mistake with almost any sensor/meter use is reading the range of measurement or value display on the screen. The cheap one you have has the measuring range 2000/20000/200000 Lux.
As a user you should have an idea on what a lux is, how is measured and how it relates to actually usable light for plants. Also helps to know how to use the device(user manual)
In any case, it can at most be used for relative(comparative) measurements.
Cheers
As a user you should have an idea on what a lux is, how is measured and how it relates to actually usable light for plants. Also helps to know how to use the device(user manual)
In any case, it can at most be used for relative(comparative) measurements.
Cheers
It showed a reading of 184 x10 18" under the panel dimmed to 240 watts in center of the 3x3 area.
My plants look sick under led compared to cmh.
I had the led panels up at 10 feet 4 feet from the top of the plant canopy dimmed to 350 watts i think that was too high and made them look sick. But now there at 18" above canopy dimmed to 240 watts or 50% sure hope that fixes the problem.
There around 6 feet tall 2 weeks into bloom but still no bud site formation
I can look and tell they are not happy the position of their leaves arent right the texture of the leaves feel dry and hard, the colors are not an even green.
This never happens under cmh thats why I'm so worried the leds was a bad decision
My plants look sick under led compared to cmh.
I had the led panels up at 10 feet 4 feet from the top of the plant canopy dimmed to 350 watts i think that was too high and made them look sick. But now there at 18" above canopy dimmed to 240 watts or 50% sure hope that fixes the problem.
There around 6 feet tall 2 weeks into bloom but still no bud site formation
I can look and tell they are not happy the position of their leaves arent right the texture of the leaves feel dry and hard, the colors are not an even green.
This never happens under cmh thats why I'm so worried the leds was a bad decision
Even with forced ventilation, I think 500 watts is about all the LED power a 4 x 4 tent can take. A 3 x 3 would be 9/16's of that, or so. (3x3) vs (4 x 4)
You should get a PAR meter. Phantom by Photobio works fine. Now that the WuFlu scare has subsided, I want a touchless temp scanner for the leaves.
RobertFripp
Active member
The way I figure how many w/sq/ft is to use my Gavita 1700e as reference.
Gavita says the 645w 1700e is made for a 4 x 4 area. Its roughly 1700umol.
So I simply divide 645w x 16sq/ft, and it comes out to 40.3w sq/ft.
So in a 3 x 3 you would need 362.7w sq/ft in a 3 x 3.
9sq/ft x 40.3w sq/ft is 362.7w sq/ft.
But this is relevent only if using the best Samsung Diodes.
In veg I keep the 1700e 24 inches from canopy.
In flowering I lower it to 18 inches, and I also have a huge amount of airflow
Other than the heat, I still like a 1000w Hortilux HPS in a 4 x 4 area.
Gavita says the 645w 1700e is made for a 4 x 4 area. Its roughly 1700umol.
So I simply divide 645w x 16sq/ft, and it comes out to 40.3w sq/ft.
So in a 3 x 3 you would need 362.7w sq/ft in a 3 x 3.
9sq/ft x 40.3w sq/ft is 362.7w sq/ft.
But this is relevent only if using the best Samsung Diodes.
In veg I keep the 1700e 24 inches from canopy.
In flowering I lower it to 18 inches, and I also have a huge amount of airflow
Other than the heat, I still like a 1000w Hortilux HPS in a 4 x 4 area.
SamKingston
New member
From my experience, a 250-watt LED CB should be enough for a 3x3 room, significantly if you are only growing one plant and doing multiple LSTs. It's always better to start with a lower wattage and adjust it as needed rather than too high, risking burn or other problems. Running King Bright 480-watt QB at 60% is a good idea, and you can constantly adjust it later on, depending on how your plant responds. To grow my plants, I buy LED Grow Lights at happyhydro.com as it is convenient and designed for a small space. Best of luck with your growth!
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