Led grow light

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FourthCity

FourthCity

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I dunno I kill it with 30 watts of HLG Rspec LED's per ft2, any more without co2 would only hurt the plants, I have been growing on a medium scale since 1997, it's not my first rodeo. I can read plants & 30 watts with no co2 is the max I can run on my plants!
That light at 30 watts per sqft will still make some nice bud, I can't tell you why your plants don't want the extra light but mine seem to love it. I checked the pics in your profile and noticed that they were all of relatively compact plants that are grown in soil, they may not have the same light requirements as plants I grow in hydro that get up to 6ft tall. Its not about bigger is better, if the op is going to grow similar sized plants in soil like you than they can probably get by with less light, if they are trying to grow in hydro and take advantage of more vertical space they will want that extra wattage.
 
maximusluminous

maximusluminous

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That light at 30 watts per sqft will still make some nice bud, I can't tell you why your plants don't want the extra light but mine seem to love it. I checked the pics in your profile and noticed that they were all of relatively compact plants that are grown in soil, they may not have the same light requirements as plants I grow in hydro that get up to 6ft tall. Its not about bigger is better, if the op is going to grow similar sized plants in soil like you than they can probably get by with less light, if they are trying to grow in hydro and take advantage of more vertical space they will want that extra wattage.

half are in coco & perlite (coco loco) & half are in rockwool cubes, 6"x6"x6".. I can't get 3oz out of 1 gal containers of soil, no sir...lol, maybe 2.5 oz if everything goes perfect but 3oz + is nothing for me in coco in 1 gal pots. These plants will not veg upwards towards the lights unless they are dimmed to 50% & even then they want to bush out not up, and Im talking 24" or more of light height, if not 30", tons of crosslight instead of reflection, I mean still some reflection because there are walls, just not in a small inclosed space, my room is 9x9 & it is packed to the gills. And not all plants are the same size nor in the same 1 gal pots, some are in 3 gallon pots, sometimes I run 4 gal pots, I just make use of space with what will fit there so I will have younger less vegged plants mixed with larger longer vegged plants if one will fit a hole I have. I just ordered an autopilot 8200 so co2 is in my future (they are or were on sale on Amazon for $140 the other day). Here is what a wedding cake S1looks like in a 3 gal pot of coco loco the first week of flower & I only snipped it 1 time & no training or anything..lol. These led's make bushes! And stems go purple or red like mad, they don't under HPS tho or not much at least
 
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Munch517

Munch517

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800 watts is still only 32 watts per sqft, it will not perform as well as 1000 watts hps or led.

800w of a good led will perform much better than a 1000w hps. Per Migro's tests the best an hps can do is about 1.3 ppfd/watt, the best LEDs he's tested are at 2.2 ppfd/watt and there's better ones he hasn't tested yet. The spread on the bar lights are much better than an hid light also.
 
FourthCity

FourthCity

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800w of a good led will perform much better than a 1000w hps. Per Migro's tests the best an hps can do is about 1.3 ppfd/watt, the best LEDs he's tested are at 2.2 ppfd/watt and there's better ones he hasn't tested yet. The spread on the bar lights are much better than an hid light also.
800 watts of Mars Hydro leds vs 1000 watts of DE HPS might be close, maybe the Mars can replace it but I'm skeptical it would outperform the hps. I stand by 40 watts per sqft or 1000 watts of led as a good baseline for a 5x5.
 
Munch517

Munch517

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800 watts of Mars Hydro leds vs 1000 watts of DE HPS might be close, maybe the Mars can replace it but I'm skeptical it would outperform the hps. I stand by 40 watts per sqft or 1000 watts of led as a good baseline for a 5x5.

Migro has tested the Mars tsw and sp series lights and they've come in at 1.6 and 1.8 ppfd/watt respectively, so yes, quite more efficient than HID bulbs but not on par with lights like Fluence and HLG.

For example an LED light with 2.2ppfd/watt efficiency is 59% more efficient than the most efficient HID (1200w double ended hps). That means a 700 watt LED of that efficiency would have an equal light output to a 1200w double ended hps. My Spydr 2p is 645w and likely around 2.3-2.4 ppfd/watt, also close to equivalent with the 1200w hps. To add a personal anecdote, my lights have to be kept more than a foot above the plants without CO2, so their 645w of power provides way more light than the plants can use in that 4x4 footprint. (Since adding CO2 I keep the lights 4-6" from the tallest tops)

If you have a light that can completely cover the canopy 30w/sq ft of HLG or Fluence lighting will be plenty, if adding CO2 40-45w/ sq ft is desirable. Both requirements go up significantly with lower efficiency or poor light spread, both are key, as is proper light placement.
 
maximusluminous

maximusluminous

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Migro has tested the Mars tsw and sp series lights and they've come in at 1.6 and 1.8 ppfd/watt respectively, so yes, quite more efficient than HID bulbs but not on par with lights like Fluence and HLG.

For example an LED light with 2.2ppfd/watt efficiency is 59% more efficient than the most efficient HID (1200w double ended hps). That means a 700 watt LED of that efficiency would have an equal light output to a 1200w double ended hps. My Spydr 2p is 645w and likely around 2.3-2.4 ppfd/watt, also close to equivalent with the 1200w hps. To add a personal anecdote, my lights have to be kept more than a foot above the plants without CO2, so their 645w of power provides way more light than the plants can use in that 4x4 footprint. (Since adding CO2 I keep the lights 4-6" from the tallest tops)

If you have a light that can completely cover the canopy 30w/sq ft of HLG or Fluence lighting will be plenty, if adding CO2 40-45w/ sq ft is desirable. Both requirements go up significantly with lower efficiency or poor light spread, both are key, as is proper light placement.

well said, you are 100% dead on the money sir!
 
MarsHydroLED

MarsHydroLED

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800 watts is still only 32 watts per sqft, it will not perform as well as 1000 watts hps or led.
Sure, it can't equal to1000w hps, don't say more 800w led with 1000w led. Just for reference for the same growing areas set up. The led and hps, they are different types of light, there so many factors need to consider.
But we all know the more watt, better results
 
FourthCity

FourthCity

778
143
Migro has tested the Mars tsw and sp series lights and they've come in at 1.6 and 1.8 ppfd/watt respectively, so yes, quite more efficient than HID bulbs but not on par with lights like Fluence and HLG.

For example an LED light with 2.2ppfd/watt efficiency is 59% more efficient than the most efficient HID (1200w double ended hps). That means a 700 watt LED of that efficiency would have an equal light output to a 1200w double ended hps. My Spydr 2p is 645w and likely around 2.3-2.4 ppfd/watt, also close to equivalent with the 1200w hps. To add a personal anecdote, my lights have to be kept more than a foot above the plants without CO2, so their 645w of power provides way more light than the plants can use in that 4x4 footprint. (Since adding CO2 I keep the lights 4-6" from the tallest tops)

If you have a light that can completely cover the canopy 30w/sq ft of HLG or Fluence lighting will be plenty, if adding CO2 40-45w/ sq ft is desirable. Both requirements go up significantly with lower efficiency or poor light spread, both are key, as is proper light placement.
A good de hps should reach or exceed 1.8 ppfd, at least thats what a few of the better manufacturers claim. Migro is also an led company that has an incentive to perform tests in a way that will make their product look better. There is no mention I could find of them testing the lights at multiple heights to get proper ppfd readings and I did not see where they evaluated any de hid lights. I think you are extrapolating your opinion based on a biased test. I do agree that some leds can outperform some hps lights per watt but it is not as cut and dry as all leds are 30% better or more than all hids like you are claiming.
 
Munch517

Munch517

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A good de hps should reach or exceed 1.8 ppfd, at least thats what a few of the better manufacturers claim. Migro is also an led company that has an incentive to perform tests in a way that will make their product look better. There is no mention I could find of them testing the lights at multiple heights to get proper ppfd readings and I did not see where they evaluated any de hid lights. I think you are extrapolating your opinion based on a biased test. I do agree that some leds can outperform some hps lights per watt but it is not as cut and dry as all leds are 30% better or more than all hids like you are claiming.

I find if odd that you accept manufacturer numbers as gospel and question a well known and respected independent tester who does mush of his testing on video and posts it publicly. I don't believe any HPS is coming close to 1.8 ppfd/watt, that's goes against every independent information I've come across (besides, every LED manufacturer makes claims higher than Migro's results also) I stick to his numbers because it's very important when making comparisons that all lights were tested with the same equipment and methodology.

I never said anything approaching "all LEDs are 30% more efficient". I listed lights I consider worth buying that are anywhere from 25-75%+ more efficient. The fan boxes and blurple LEDs (think viparspectra and old Mars Hydro) are from less than 1.0 up to 1.3 ppfd/ watt, T5s are around 0.7-0.8 ppfd/watt.

I don't care if you want to ignore data and don't want to believe, just please don't run around here giving others bad information. Lights are one of the only things in growing right now that can be easily quantified and reliably compared. There doesn't need to be guess work and extrapolation, real data is out there for everyone to see.
 
FourthCity

FourthCity

778
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I find if odd that you accept manufacturer numbers as gospel and question a well known and respected independent tester who does mush of his testing on video and posts it publicly. I don't believe any HPS is coming close to 1.8 ppfd/watt, that's goes against every independent information I've come across (besides, every LED manufacturer makes claims higher than Migro's results also) I stick to his numbers because it's very important when making comparisons that all lights were tested with the same equipment and methodology.

I never said anything approaching "all LEDs are 30% more efficient". I listed lights I consider worth buying that are anywhere from 25-75%+ more efficient. The fan boxes and blurple LEDs (think viparspectra and old Mars Hydro) are from less than 1.0 up to 1.3 ppfd/ watt, T5s are around 0.7-0.8 ppfd/watt.

I don't care if you want to ignore data and don't want to believe, just please don't run around here giving others bad information. Lights are one of the only things in growing right now that can be easily quantified and reliably compared. There doesn't need to be guess work and extrapolation, real data is out there for everyone to see.
I am perfectly fine with supporting my statements or agreeing to disagree with someone but I never called your information bad just because it doesn't line up with mine. I've said a few things here, mostly supported by anecdotal evidence, what specific information do you think is bad? Besides, you are really misrepresenting what I said, I don't accept manufacturers numbers as gospel, I literally went out of my way to call their numbers "claims" as opposed to fact. I'm also not ignoring any data, before commenting I clearly looked at the tests you referenced and mentioned what I think are some valid concerns about the quality and completeness of that data. Migro is a manufacturer of led lights, they can not be considered an independent tester any more than mars hydro, hlg, gavita, etc. By sticking to Migro's numbers like you said, how are you considering all the data?

Saying that the lights can easily be quantified and compared based off the data that's out there is an oversimplification that doesn't take into consideration all the nuances between different test setups, grow setups, and other conditions. I never meant to get us on an hps vs led tangent and I already conceded earlier that I should have been more specific in the statement that started this. I was really just trying to point out that its not as easy as replacing an hps with a lower wattage led and getting better results but the main point was that regardless of led or hid, 40 watts per square foot is a good baseline. Personally, my grow is almost entirely led, I agree that generally they can be superior to hps but when compared watt for watt. Having gradually switched from hps to completely led for my 4x12 flowering area I can say that despite likely being less efficient than the leds the hps did not produce lower quality buds or yields for me. That being said, none of my hps had a dimmable ballast and the leds with their dimmers can certainly perform as well the hps, like I said before, for most of the grow on lower power which is a huge advantage.
 
Munch517

Munch517

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I am perfectly fine with supporting my statements or agreeing to disagree with someone but I never called your information bad just because it doesn't line up with mine. I've said a few things here, mostly supported by anecdotal evidence, what specific information do you think is bad? Besides, you are really misrepresenting what I said, I don't accept manufacturers numbers as gospel, I literally went out of my way to call their numbers "claims" as opposed to fact. I'm also not ignoring any data, before commenting I clearly looked at the tests you referenced and mentioned what I think are some valid concerns about the quality and completeness of that data. Migro is a manufacturer of led lights, they can not be considered an independent tester any more than mars hydro, hlg, gavita, etc. By sticking to Migro's numbers like you said, how are you considering all the data?

Saying that the lights can easily be quantified and compared based off the data that's out there is an oversimplification that doesn't take into consideration all the nuances between different test setups, grow setups, and other conditions. I never meant to get us on an hps vs led tangent and I already conceded earlier that I should have been more specific in the statement that started this. I was really just trying to point out that its not as easy as replacing an hps with a lower wattage led and getting better results but the main point was that regardless of led or hid, 40 watts per square foot is a good baseline. Personally, my grow is almost entirely led, I agree that generally they can be superior to hps but when compared watt for watt. Having gradually switched from hps to completely led for my 4x12 flowering area I can say that despite likely being less efficient than the leds the hps did not produce lower quality buds or yields for me. That being said, none of my hps had a dimmable ballast and the leds with their dimmers can certainly perform as well the hps, like I said before, for most of the grow on lower power which is a huge advantage.

To be clear, I'm not trying to argue, just make to make sure that others who stumble across this get good info. To list some specific points of disagreement:

I disagree with you on your claim that 800w of LED can't match 1000w hps. Even mediocre LEDs can do that. With the best LEDs 600w can equal a 1000w HPS.

40w/sq ft of a good LED is not necessary without CO2. For an anecdote, my Spydr 2p provides 40.1w/sq ft and before I added CO2 I had to keep the light dimmed or keep it more than a foot from the tops to prevent damage. It would be better to leave watts out of it and say that you should shoot for a 1000ppfd as evenly as possible across the canopy without CO2 and as much as 1500ppfd with CO2.

The reason to stick with Migro's numbers is that the efficiency numbers are only valid if the testing was done the same. The value in the efficiency numbers is more for relative numbers than for absolute figures. Different testing methodologies will produce different numbers but they should be similar in relation to each other. Amongst people in the know Migro's numbers seem well accepted and I personally don't see any significant flaws in his methodology.

It's completely possible to set up LED lights wrong and not get the benefit of their greater efficiency. The figures given are for hanging the light at a proper height in a properly sized area with reflective walls.
 
maximusluminous

maximusluminous

233
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A good de hps should reach or exceed 1.8 ppfd, at least thats what a few of the better manufacturers claim. Migro is also an led company that has an incentive to perform tests in a way that will make their product look better. There is no mention I could find of them testing the lights at multiple heights to get proper ppfd readings and I did not see where they evaluated any de hid lights. I think you are extrapolating your opinion based on a biased test. I do agree that some leds can outperform some hps lights per watt but it is not as cut and dry as all leds are 30% better or more than all hids like you are claiming.

Migro tested the Gavita DE 1000 HPS & it was 1.4 Efficiency, here is a screen shot of the results in the video that he did with it vs his migro 640 watt set up. The 1000 DE gets beat bigly by his 640 watt LED set up. NOTE that he got the data wrong in this. He has the Miigro & Gavita PPFD results backwards, the gavita is higher PPFD but only by a little & at way more power consumption
 
Screen Shot 2020 02 13 at 72003 PM
FourthCity

FourthCity

778
143
The reason to stick with Migro's numbers is that the efficiency numbers are only valid if the testing was done the same. The value in the efficiency numbers is more for relative numbers than for absolute figures. Different testing methodologies will produce different numbers but they should be similar in relation to each other. Amongst people in the know Migro's numbers seem well accepted and I personally don't see any significant flaws in his methodology.
Migro tested the Gavita DE 1000 HPS & it was 1.4 Efficiency, here is a screen shot of the results in the video that he did with it vs his migro 640 watt set up. The 1000 DE gets beat bigly by his 640 watt LED set up. NOTE that he got the data wrong in this. He has the Miigro & Gavita PPFD results backwards, the gavita is higher PPFD but only by a little & at way more power consumption
The minimum recommended hanging distance from Gavita is 3.2 feet, I wonder why Migro tested it at 2 feet? Why not test each light at multiple heights over varying footprints so we have some useful information? Is it because the light from leds is more concentrated and ppfd drops more quickly compared to hids as the fixture is moved away from the sensor? I don't think his methodology is necessarily flawed, my point is that he is only collecting and displaying a limited amount of information, that while accurate, does not nearly convey all the strengths and weaknesses of each light.
 
maximusluminous

maximusluminous

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The minimum recommended hanging distance from Gavita is 3.2 feet, I wonder why Migro tested it at 2 feet? Why not test each light at multiple heights over varying footprints so we have some useful information? I don't think his methodology is necessarily flawed, my point is that he is only collecting and displaying a limited amount of information, that while accurate, does not nearly convey all the strengths and weaknesses of each light.

he sets the lights at a hight where they make as close to 1000ppfd across the canopy as possible, so it's what ever hight that takes to = an average close to 1000ppfd. Obviously he found that at 3.2 ft the gavita did not get near 1000ppfd since at 2ft it wasn't even 1000 ppfd & ppfd isn't going to go up if you raise the light, its gonna go down not up.
 
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FourthCity

FourthCity

778
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he sets the lights at a hight where they make as close to 1000ppfd across the canopy as possible, so it's what ever hight that takes to = an average close to 1000ppfd. Obviously he found that at 3.2 ft the gavita did not get near 1000ppfd
Look closely, he doesn't even test them in the same tent! What height was the migro hung at? Must not have been important. This isn't science, its marketing. If he did the same test with both lights in the same tent at the 1 meter height recommended by Gavita I would bet the results at least start to move in the other direction.
 
maximusluminous

maximusluminous

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Look closely, he doesn't even test them in the same tent! What height was the migro hung at? Must not have been important. This isn't science, its marketing. If he did the same test with both lights in the same tent at the 1 meter height recommended by Gavita I would bet the results at least start to move in the other direction.

if its marketing its pretty shitty because lots of lights he tests beat his migro lights, your idea of marketing must mean he is trying to sell others equipment.. did you watch the video? He is a straight up as it gets in the light testing world, I have followed him for years because he tells the truth! Even his tests show the fluence lights to be the best of the best. He tests everything from cheap crap led's to the best of the best, his migro stuff is top 30% but still far from the best of what he tests
 
Munch517

Munch517

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43
Look closely, he doesn't even test them in the same tent! What height was the migro hung at? Must not have been important. This isn't science, its marketing. If he did the same test with both lights in the same tent at the 1 meter height recommended by Gavita I would bet the results at least start to move in the other direction.


Of course if you were to put a 100w LED at 3' over the canopy it wouldn't result in good numbers. The hps light hung at an LED-appropriate light would destroy the plants. And I can't imagine how raising a individual light would cause its efficiency to go up, however I guess I won't die on that hill without real data to go off. I could see a case being made for a higher HPS efficiency with stadium-style lighting or possibly in a high bay grow where there's many lights hung high and they benefit from the cross lighting. I still doubt either scenario would yield better results than a decent LED.
 
maximusluminous

maximusluminous

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Some things he says are not exactly true. Such as about dimming, it is true the led's run more efficiently when dimmed but the flip side is led drivers only hits their highest efficiency rating at full power. like if your driver is 94% efficient that 94% rating is at 100% power, at 70% power that # may drop to 85% so you are losing some of the overall system efficiency in all reality.

Also the california light works LED's that he claims should work more efficiently because it has the targeted red & blue spectrum with less white diodes thus less over all green & yellow in the spectrum do not work more efficiently than say 3500K diodes with added 660nm reds. HLG & other all white with added reds will waste the california light works watt per watt.

I could go on but he has some major flaws, this is outdated info today IMHO, the beginner 101 basics are pretty accurate but his beyond basic "science" is flawed which has been proven since this video was made in 2018. 3000k to 3500k whites diodes with 660nM diodes added or supplemented FTW. other LED combos work too but I'm pretty sure white diodes rule the current market for a reason. By his science blurples should work great, outperform anything, but they don't, not even close!
 
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