A customer has a question and I hope we can get some opinions on it, thanks.
I have a 1200 and 2 600 but idk if I need all that . I know the 1200 wall watts r 250 but idk the 2 600’s and idk if that even matters? I need some help
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Join us there are many members here that would love to help you out
Rule of thumb is 50 true watts of light per square foot of canopy
There are other factors as well like spectrum and par rating ect
But if you aim to be in that 50 watt range you should do well
You want a minimum off 600 watts of light for flowering
Foot print is also a factor that needs to ne concidered
Happy growing 
CB
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… and always look at the power drawn from the plug, not advertised watts. Most advertised 1000 watt or higher units draw 200 watts +-
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What type of led do you have? With legit led- qb or cobs it’s going to be way lower than 50 Watts. 50 watts of blurple leds yes. This forum has taught me a lot. Go to hlg and look at specs.
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As well as I … Lighting is hyper critical. It is also hyper subjective on “which does what better when” … The lighting subject is loaded… Too many variables to say “QB builds are better than pre-fab COB’s are better than HPS/MH, CF, Ceramic, etc…”
What works for me may not work for you and vice versa. Subjective…
Anyone who says “this technology is better” is full of …
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It’s science. Buy a light meter and a kil-o-watt.
Also there are bins leds go in. So saying a pos led is equal to a top bin doesn’t make sense. Both work yes. How they grow can be can be subjective. But wattage used to light emitted spectrum emmmited etc. not subjective. Facts. Math.
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With the 50 watt rule you wont go wrong
Can you get away with less maybe
But this individual already owns lights and with those the 50 watt rule works
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I agree. If those lights are blurple the watts rule is true.
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Not in my opinion. Cmh is better than hps on just about every account. The only place hps would be better is if you need less light and more heat. Shifting from hid to led is maybe more subjective because differences in emitted wavelengths. But it’s proven and measurable that photon efficacy is higher with a lot of leds. Whether or not higher efficacy is important to the individual is the only real questionable subject.
For someone to say “I don’t care about how inefficient these lights are, I like them better” does not make them as good as other options.
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Thanks for your awesome work @ILGM.Zoe
Thanks for the tag @Countryboyjvd1971, my dear friend 
Dear customer, like my fellow growers mentioned, it’s preferably will be much easier for us to give you an adequate support by knowing a little bit more of your light source and it’s characteristics and witch brand it is.
None less , If i understand you well, you’re asking what’s the difference between 1-1200 watt LED light fixture and 2- 600 watt ones.
All depends on your growing space, it’s square feet size…
1-1200 watt will cover less footprint than 2-600, but will have more PPF and PPFD (light intensity) in the center of it’s footprint, right under the light fixture.
In an other hand, 2-600 watt will have more footprint combine together , cover more space, but will have a little less PPF and PPFD but a more even one in your growing space.
Or, you can use the 600 watt ones for side light supplemental for the 1200 watt one, on each side of it.
In hope that’s responding to your questioning, why not join the Bergman’s Lab or the ILGM forums, you’ll find a lot of capable growers that are willing to share their knowledge…
~Al 
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So If I have a 1500 watt King Plus LED light fixture that is made with 10 watt LED’s but the light fixture only uses 265 watts and I was wanting to use it for a 3.75 x 3.75 grow area! So the grow area is 14 Sq ft ! So if you divide 265 by 14 that equals 18.92 watts per Sq ft! Therefore you would think I don’t have enough wattage! But the manufacture say’s it will cover a 4 x 5.5 ft area so I thought a 3.75 x 3.75 area would be Ok! Am I wrong?
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Here’s a good way of thinking about it @Rick4. The manufacturer said it used 10 watt diodes yet math tells you they’re only running at around 0.5 watts. So why would they spend the money putting bigger diodes in the light then barely run them at a fraction of their capacity? Answer is most likely they lied about what’s in the light. Just like they stretched the truth on how much space it’ll cover. Now having said that it’ll probably grow plants but the question is will they grow quality plants? I’m not an expert so take from this what you will but I don’t like being lied to by manufacturers. I would err on the side of over doing it rather than under when it comes to cannabis. There’s lots of pictures around here of what light weight, airy looking buds that come from not enough light.
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I have a 1200 watt King and it pulls 245 from the wall. It is a good light for a small area - 2x2 screened. A little lacking on penetration but two of them in a small SCRoG would work ok.
Don’t go by the KingLed info on what it can do. I think they say it replaces an 800 watt MH/HPS which is BS advertising
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Yes i do feel it is lacking but with that said you probably can grow a whole crop under it
Buds will most likely be airey or fluffy due to lack of light if you doubled up thatvwouls be better ?
I ran 2 -400 cobs that draw 197 w ea plus two 300 watt led fixtures that draw 148 watts at wall
In a 4x4 tent when i grew in a tent
Biggest problem with the cheaper led fixtures is penetration so most of is will run about 18 inches when in flower from canopy to assist with the issue which in turn lower the foot print
That light most likely covers a 4x4 area at 33 inches above ?
When I originally came indoors I figured out fast that i needed more light and keeped buying lol
Of your planning on growing dor a long rime
Building your oren is definitely something ro consider before you dump alot of $ on cheaper lighting
I only veg under led ar rhis point i flower under a 630 watt lec/ mch fixture on a light mover now
Sorry for the delayed answer
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That’s pretty sad to have 265 watts out of what is supposed to be 1500 watts of light. I have 3 of the 600w Chinese Amazon lights and they draw 285 watts with the Bloom switch on. You really will need 2 of them for a 3.75 x 3.75 space. I use 2 of them in my veg room for a 2x4 area. I got sick of low yields and airy buds so I built my own light for flowering @Rick4
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You’re still running those passively right? What kind of sink temps are you seeing?
Not passively. 2 clip on fans to keep the canopy heat down. Without fans they run about 130°. With fans, below 90°. The heatsink just needs a little air to make a huge difference. I give up 40 watts for cooling
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This year was my first use of led. I used 600w full spectrum growing ak-47 in the tent method. It worked just like mh or mv without the heat but all the spectrum of the sun. The smoke was awesome … nice tight but fluffy buds. The trim made some awesome brownies that helped me sleep and my pains were gone for some time from one brownie. I’m satisfied with my new system…
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