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Old 01-08-2012, 01:04 AM   #1
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Default LED Lighting Compendium

This thread is here to try and keep new and seasoned aquarists informed about LED lighting. Please post any information, especially relating to PAR vs Distance you have for the various LED lighting fixtures and emitters out there. I will add more information to the top post as people throw it in here. Please provide source links wherever possible.

Please do not post here asking for suggestions about a certian light or recommendations for what light to choose. This is a place for people to come and find actual information about commercial LED fixtures. If you want some suggestions, make a new thread in the lighting forum. This serves the dual purpose of not cluttering this thread and your issue getting more exposure for a suggestion. Thanks!

Deciphering This Thread
PAR Values(Source) - Thanks Gnomecatcher for the suggestion!
Values between 10-30 are considered low light.
Values between 30-80 are considered medium light.
Values between 80-120 are considered high light.
Keep in mind that these values are what is currently accepted by the community as accurate, and aren't set in stone.

Symbols
- Fixture designed for marine applications. This can be a problem in terms of high output or bad color for planted tanks.
- Fixture designed for freshwater planted applications. You shouldn't have to worry about output or color with these.
AquaIllumination Sol
PAR Data(Source) PAR Vs. Distance from source
400+ PAR @ 24"
300 PAR @ 30"
200 PAR @ 36"
Notes: Above information doesn't really do this fixture justice. Check out the source link, gives spectral output and PAR vs. distance with coverage. This fixture is meant for marine setups, so has very high PAR values. Dimming or raising the light high above the surface would be necessary for a planted setup.

AquaticLife LED 0.5W Expandable Fixtures
PAR Data not available
Notes: In response to an email i sent out, Dave Troop at AquaticLife responded saying their lights don't put out enough for plants, and are only meant for accent lighting or fish only setups (Source).

Current TrueLumen Pro LED StripLight
PAR Data(Source) PAR Vs. Distance from source
350 PAR @ surface
96 PAR @ 6"
57 PAR @ 12"
42 PAR @ 18"
31 PAR @ 24"
Notes: Numbers are for a single fixture. The source link shows numbers for multiple fixtures configured like a T5 setup as well, worth checking out.

E.Shine Systems 3G LED Aquarium Lights
PAR Data(Source)
Notes: The different configurations of this light series are much too extensive to list in this thread. Click on the source link for a full list of the 3G LED fixtures offered by E.Shine. Each page has very comprehensive PAR data, so just poke around a bit.

E.Shine Systems Aqua Washer
PAR Data(Source)
Notes: Complete graphical PAR data is provided in the source link for this fixture.

E.Shine Systems 60W CREE Classic
PAR Data(Source)
Notes: Complete graphical PAR data is provided in the source link for this fixture. Looks to be very high powered, more suited for marine use. Could use for plants if it was hung fairly high above the tank, or good for deep tanks.

Ecoxotic Panorama Freshwater Module
PAR Data(Source) PAR Vs. Distance from source
161 PAR @ surface (3" through air)
101 PAR @ 7"
60 PAR @ 12"
36 PAR @ 18"
Notes: One should easily cover the footprint of a 10 gallon tank with medium-high light.

Ecoxotic Stunner Strip
PAR Data(Source) PAR vs. Distance from source
105 PAR @ surface (3" through air)
86 PAR @ 7"
71 PAR @ 12"
59 PAR @ 15"
49 PAR @ 18"
Notes: Please note that the above reading is for a 4 strip array. I don't know why the testers did this since it gives us no real basis on which to judge this fixture. Good catch Erica.

Finnex FugeRay
PAR Data(Source) PAR vs. Distance from source
10" fixture: 49 PAR @ 6", 18 PAR @ 12", 9 PAR @ 18"
12" fixture: 62 PAR @ 6", 25 PAR @ 12", 13 PAR @ 18"
Notes: Amazingly low cost for an LED fixture that puts out medium light for nano tanks. Nice slim design, too. It's a good idea to check out the source link on this one, gives offset PAR values so coverage can be approximated. One of the easiest to read PAR charts i've seen. Also comes equipped with blue moonlights. Big thanks to Lowe for the data on these.

Finnex Ray II
PAR Data(Source) PAR vs. Distance from source
16" fixture: 130 PAR @ 6", 49 PAR @ 12", 27 PAR @ 18"
18" fixture: 153 PAR @ 6", 72 PAR @ 12", 37 PAR @ 18"
24" fixture: 179 PAR @ 6", 87 PAR @ 12", 55 PAR @ 18"
Notes: Great value priced fixture for various sized tanks. It's a good idea to check out the source link on this one, gives offset PAR values so coverage can be approximated. One of the easiest to read PAR charts i've seen. Big thanks to Lowe for the data on these.

Innovative Marine SKKYE Lights
PAR Data(Source)
Just look at the source link on this one, PAR data is very well explained.

Kessil A150 LED Aquarium Light
PAR Data(Source) PAR vs. Distance from source
2888 PAR @ 0"
2000 PAR @ surface (4" through air)
400-500 PAR @ 8"
80-90 PAR @ 15"
Notes: Very powerful lights, designed for reef applications. If you go through the thread in the source link, there is a lot more information pertaining to this light. An example I found interesting was the 20g long lit with a single one of these lights hung pretty high above the tank, and still growing corals (view here). Credit for PAR data goes to Frick.

Kessil A150W Amazon Sun
PAR Data(Source 1, Source 2) PAR vs. Distance from source
56 PAR @ 18"
42 PAR @ 21"
34 PAR @ 24"
Notes: Seem to be about perfect for getting medium light to most medium sized aquariums. Great coverage for such a small light. Credit for PAR data goes to propsi.

Marineland Single Bright
PAR Data(Source) PAR vs. Distance from source
18-24" fixture: 8 PAR @ 12", 3 PAR @ 24"
24-36" fixture: 10 PAR @ 12", 4 PAR @ 24"
36-48" fixture: 11 PAR @ 12", 4.5 PAR @ 24"
48-60" fixture: 16 PAR @ 12", 6 PAR @ 24"
Notes: Probably not suitable for even low light plants unless the tank is very shallow.

Marineland Double Bright
PAR Data(Source) PAR vs. Distance from source
18-24 inch fixture: 30 PAR @ 12", 17 PAR @ 24"
24-36 inch fixture: 35 PAR @ 12", 19 PAR @ 24"
36-48 inch fixture: 54 PAR @ 12", 26 PAR @ 24"
48-60 inch fixture: 73 PAR @ 12", 35 PAR @ 24"
Notes: Should provide low light for most tanks, depending on fixture size.

Marineland Reef Capable
PAR Data(Source) PAR vs. Distance from source
1876 PAR @ surface
253 PAR @ 6"
170 PAR @ 12"
110 PAR @ 18"
80 PAR @ 24"
Notes: Would probably have to be hung at least 1 foot above most tanks to prevent lots of algae. Great for high light on a tall tank as well. Thanks goes out again to AquaNerd blog, much better than the information in Marineland's catalog.

Maxspect Mazarra LED Lighting System
PAR Data(Source) PAR vs. Distance from source
350 PAR @ 20"
Notes: Check out the source link on this one, gives coverage data as well. This system is designed for reef applications, so put out very, very high PAR. They use the newest CREE XM-L emmiters, which are very powerful. Probably too powerful for anything a plant enthusiast could use. Click here for an image of what a reefer has done with this setup, and the extremely high PAR he's getting. Credit for PAR reedings on that image goes to Acrotrdco.

TMC AquaBeam 1500XG Ocean White
PAR Data(Source) PAR Vs. Distance from source
231 PAR @ surface (7 through air)
161 PAR @ 10
104 PAR @ 14
78 PAR @ 19
52 PAR @ 25
Notes: Uses 10 x 9000K Cree XP-G diodes.

TMC GroBeam 1000 Natural Daylight
PAR Data(Source) PAR Vs. Distance from source
195 PAR @ surface (7 through air)
120 PAR @ 10
80 PAR @ 14
52 PAR @ 19
41 PAR @ 25
Notes: Uses 10 x 6500K Cree XP-E Compact PowerLEDS.

WingoLED Fluval Edge Savior
PAR Data(Source)
Notes: Click on the source link for par data here, shows PAR values for various points at the bottom of the aquarium. Very nice solution for the Fluval Edge line of aquariums, where space and coverage are in inherent issue with this tank design. Credit for PAR data goes to WingoAgency.

WingoLED PAR38 Bulbs
PAR38 15x1W WingoLED DayLight 12,000K
PAR38 12x1W WingoLED TriBand 60 degree
PAR38 18x1W WingoLED Perfect Sprectrum
PAR38 15x1W WingoLED DayLight 6,700K
Notes: Just click on the links for these individually, great graphical par data is provided. Credit for PAR data goes to WingoAgency.
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LED Lighting Compendium
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Originally Posted by Ludwig van Beethoven
Don't only practice your art, but force your way into it's secrets, for it and knowledge can raise men to the divine.

Last edited by samamorgan; 04-23-2012 at 11:46 PM..
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Old 01-08-2012, 01:05 AM   #2
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Not all spectrums are created equal!
Analyzing photosynthetically active radiation (PUR)

Please keep in mind that the following is purely informational, and should be taken very lightly if at all when considering an LED fixture purchase!

One of the reasons LEDs can be so much more efficient than T5, compact flourescent, and even metal halide is spectrum output. The chlorophyll pigment is green in color, which means that it reflects the green spectrum of light to our eyes so we see it as green. This means that it absorbs all other spectrums of visible light. Check out this graph:
Name:  Absorbtion Spectra.jpg
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As you can see, plants absorb visible light very well between ~400-500nm and ~650-700nm. The absorbtion rate drops off significantly in the green and yellow spectrums. Here are some LED emmiter comparisons in terms of specrum. Big thanks to redfishsc for doing the footwork on this. Notice that the warm white LEDs put out significantly lower blue spectrum spikes, but much higher red-yellow spectrum spikes. Essentially this tells us that cool white LEDs are almost always better for plant growth.

LEDs put out very specific spectrums of light, which are defined by the manufacturer. LED manufacturers can fine tune emmiters to put out exactly the spectrum specified by the client. Since PAR meters measure light between 400-700nm, an LED array putting out less par than a broad spectrum flourescent fixture may actually be putting out more photosynthetically usable radiation (PUR).

Why is this concept important?
Say two LED emmiters read around 100 PAR on a meter. The first LED spikes highest in the 550nm range. The second LED spikes highest in the 450nm range. So while both emmiters have the same PAR value, emmiter two would actually grow plants very well because it is in a range that can be absorbed by the plant, while emmiter one would probably keep plants limping along, if they could even survive.
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Old 01-08-2012, 01:06 AM   #3
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Placeholder.
__________________
LED Lighting Compendium
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Quote:
Originally Posted by Ludwig van Beethoven
Don't only practice your art, but force your way into it's secrets, for it and knowledge can raise men to the divine.

Last edited by samamorgan; 01-14-2012 at 08:53 PM..
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Old 01-15-2012, 03:05 AM   #4
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Originally Posted by samamorgan View Post
Not all spectrums are created equal!
Analyzing photosynthetically active radiation (PUR)

One of the reasons LEDs can be so much more efficient than T5, compact flourescent, and even metal halide is spectrum output. The chlorophyll pigment is green in color, which means that it reflects the green spectrum of light to our eyes so we see it as green. This means that it absorbs all other spectrums of visible light. Check out this graph:

As you can see, plants absorb visible light very well between ~400-500nm and ~650-700nm. The absorbtion rate drops off significantly in the green and yellow spectrums.

LEDs put out very specific spectrums of light, which are defined by the manufacturer. LED manufacturers can fine tune emmiters to put out exactly the spectrum specified by the client. Since PAR meters measure light between 400-700nm, an LED array putting out less par than a broad spectrum flourescent fixture may actually be putting out more photosynthetically usable radiation (PUR).

Why is this concept important?
Say two LED emmiters read around 100 PAR on a meter. The first LED spikes highest in the 550nm range. The second LED spikes highest in the 450nm range. So while both emmiters have the same PAR value, emmiter two would actually grow plants very well because it is in a range that can be absorbed by the plant, while emmiter one would probably keep plants limping along, if they could even survive.
Just because plants are green doesn't mean they reflect all of the green parts of the light spectrum. It means they reflect more green than red, primarily, and blue secondarily. Another reason plants look green is that our eyes are very sensitive to green, but not at all sensitive to red. But, plants absorb all parts of the spectrum to some extent. Most LEDs don't have the very high spikes in output that we see with fluorescent lights. The ones I have seen have a peak, for sure, but it is a broad one, and there is still a lot of light emitted that isn't in that peak.

Until we know how much PAR we are getting with various lights in various configurations it makes little sense to try to complicate matters by also worrying about PUR. PUR was of much more importance when it was hard to get enough light to grow plants, and anything that would increase the amount of usable light we were getting from a light fixture was something good to pursue. Now, the biggest lighting problem we have is having way more light (PAR) than we can easily use on our tanks. So PUR becomes much less relevant.

I find the collecting of PAR data for various manufactured LED light fixtures very useful, and I hope we can expand it eventually to include all such lights that are available. Let's not complicate it.
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Old 01-15-2012, 03:42 AM   #5
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I actually added this because i see a lot of questions like "why wont my incandescent/actinic lights grow plants? I've got enough wattage!"

I know that light reflection and human eye perception is much more complicated that i made it out to be, but actually adding that information in there would just complicate the idea i was trying to get across. You can see in the chart that the other spectrums are absorbed by the plant to a point, but not at nearly the rate that the proper spectrums are.

Also, wouldnt this factor in quite a bit from emmiter to emmiter? I know a lot of fixture manufacturers order patented emmiters from cree that put out the spectrums they want. Those patented emmiters vs a regular cool white would be significantly different in useable plant light, right?

If you really think this complicates things too much or its really just not useful end-user information, i'd be glad to take it down. If you think it is useful and can think of a way to improve the information in a concise way, i'm all for editing it. I'd like this thing to be a knowledge base from the community - for the community, not just from my point of view.
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Originally Posted by Ludwig van Beethoven
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Old 01-24-2012, 12:29 AM   #6
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Originally Posted by Hoppy View Post
Just because plants are green doesn't mean they reflect all of the green parts of the light spectrum. It means they reflect more green than red, primarily, and blue secondarily. Another reason plants look green is that our eyes are very sensitive to green, but not at all sensitive to red. But, plants absorb all parts of the spectrum to some extent. Most LEDs don't have the very high spikes in output that we see with fluorescent lights. The ones I have seen have a peak, for sure, but it is a broad one, and there is still a lot of light emitted that isn't in that peak.

Until we know how much PAR we are getting with various lights in various configurations it makes little sense to try to complicate matters by also worrying about PUR. PUR was of much more importance when it was hard to get enough light to grow plants, and anything that would increase the amount of usable light we were getting from a light fixture was something good to pursue. Now, the biggest lighting problem we have is having way more light (PAR) than we can easily use on our tanks. So PUR becomes much less relevant.

I find the collecting of PAR data for various manufactured LED light fixtures very useful, and I hope we can expand it eventually to include all such lights that are available. Let's not complicate it.

I'm a little confused. I see a lot of reefers and lighting companies use PUR for LED comparison. Not saying it's right, just an observation. TMC, for example, boasts it's PUR ratings, and they seem to be regarded as one of the best manufacturers. At least they've paid rights to use the most advanced patents. They don't score very high on the PAR values, based on this thread.


Are you suggesting that because LEDs emit a broad, even spectrum, any light in the green range which is not utilized does not weigh heavily on the PUR rating as say a fluorescent light which spikes in the green? I think I understand the logic, but it may be swaying results more than "nominally."
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Old 01-24-2012, 01:26 AM   #7
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I'm a little confused. I see a lot of reefers and lighting companies use PUR for LED comparison. Not saying it's right, just an observation. TMC, for example, boasts it's PUR ratings, and they seem to be regarded as one of the best manufacturers. At least they've paid rights to use the most advanced patents. They don't score very high on the PAR values, based on this thread.


Are you suggesting that because LEDs emit a broad, even spectrum, any light in the green range which is not utilized does not weigh heavily on the PUR rating as say a fluorescent light which spikes in the green? I think I understand the logic, but it may be swaying results more than "nominally."
I think they are arguing that they don't have a way of testing PUR, so that aren't considering it. I would tend to lean towards the spectrum of light being critical, so I'd love to see more PUR information. I suggested possibly using various photographic filters to try to tease out this information (if in a very crude way).
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Old 01-24-2012, 02:05 AM   #8
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LEDs don't emit a broad, even spectrum. They emit fairly spiky spectrums, and only emit visible wavelengths. this is unlike MH and flourescent, which emit lots of ultraviolet and infrared.

LED spectrum analysis is fairly well documented in post #2, click the link in there to see.
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Old 01-16-2012, 08:38 PM   #9
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Originally Posted by samamorgan View Post
Not all spectrums are created equal!
Analyzing photosynthetically active radiation (PUR)

One of the reasons LEDs can be so much more efficient than T5, compact flourescent, and even metal halide is spectrum output. The chlorophyll pigment is green in color, which means that it reflects the green spectrum of light to our eyes so we see it as green. This means that it absorbs all other spectrums of visible light. Check out this graph:
Attachment 40237
As you can see, plants absorb visible light very well between ~400-500nm and ~650-700nm. The absorbtion rate drops off significantly in the green and yellow spectrums.

LEDs put out very specific spectrums of light, which are defined by the manufacturer. LED manufacturers can fine tune emmiters to put out exactly the spectrum specified by the client. Since PAR meters measure light between 400-700nm, an LED array putting out less par than a broad spectrum flourescent fixture may actually be putting out more photosynthetically usable radiation (PUR).

Why is this concept important?
Say two LED emmiters read around 100 PAR on a meter. The first LED spikes highest in the 550nm range. The second LED spikes highest in the 450nm range. So while both emmiters have the same PAR value, emmiter two would actually grow plants very well because it is in a range that can be absorbed by the plant, while emmiter one would probably keep plants limping along, if they could even survive.
Would it be possible to roughly estimate this by using green and yellow filters? If you were to get some photographic filters that block the green and yellow light that aren't all that useful, you might get a better idea of the PUR values of these LEDs.
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Old 01-16-2012, 09:38 PM   #10
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Originally Posted by galabar View Post
Would it be possible to roughly estimate this by using green and yellow filters? If you were to get some photographic filters that block the green and yellow light that aren't all that useful, you might get a better idea of the PUR values of these LEDs.
That's an interesting idea. I honestly don't know if that would work or not, but it sounds reasonable. My thought is: if it was really that simple, wouldnt the manufacturers already have done this to their sensors?
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Old 01-16-2012, 09:49 PM   #11
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Here is the response i got from Kessil:
Quote:
Hello Sam,

Thank you for presenting us with this opportunity.

We currently do not have official PAR measurements. There are people who have done so and I can include a link. What we have found is that the value even between units that perform the same differs greatly. We also see that different meters have different results and some do not measure UV or near UV. This is one of the reasons we spend over 1 year of independent testing on reef tanks, and we allowed our local stores in the SF bay area to test first hand as well.

I hope this link helps and feel free to let me know if you have any questions. I get a lot of feedback that Post #10 & #114 are very helpful to end users. http://www.reefcentral.com/forums/sh...2040877&page=5

Best Regards,

David Lowry
Sales Manager
Oddly enough, i found post #71 to be more relevant.
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Old 01-17-2012, 08:02 PM   #12
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Would it be possible to roughly estimate this by using green and yellow filters? If you were to get some photographic filters that block the green and yellow light that aren't all that useful, you might get a better idea of the PUR values of these LEDs.
Quote:
Originally Posted by samamorgan View Post
That's an interesting idea. I honestly don't know if that would work or not, but it sounds reasonable. My thought is: if it was really that simple, wouldnt the manufacturers already have done this to their sensors?
Does anyone have a PAR meter and a few photographic filters? Maybe put a green filter over the PAR meter probe and see what they get with various light sources?
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My 10 gallon with PAR30 LED: http://www.youtube.com/watch?v=8rbms5asKmA
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Old 01-19-2012, 01:44 PM   #13
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Originally Posted by samamorgan View Post
Not all spectrums are created equal!
Analyzing photosynthetically active radiation (PUR)

One of the reasons LEDs can be so much more efficient than T5, compact flourescent, and even metal halide is spectrum output. The chlorophyll pigment is green in color, which means that it reflects the green spectrum of light to our eyes so we see it as green. This means that it absorbs all other spectrums of visible light. Check out this graph:
Attachment 40237
As you can see, plants absorb visible light very well between ~400-500nm and ~650-700nm. The absorbtion rate drops off significantly in the green and yellow spectrums.

LEDs put out very specific spectrums of light, which are defined by the manufacturer. LED manufacturers can fine tune emmiters to put out exactly the spectrum specified by the client. Since PAR meters measure light between 400-700nm, an LED array putting out less par than a broad spectrum flourescent fixture may actually be putting out more photosynthetically usable radiation (PUR).

Why is this concept important?
Say two LED emmiters read around 100 PAR on a meter. The first LED spikes highest in the 550nm range. The second LED spikes highest in the 450nm range. So while both emmiters have the same PAR value, emmiter two would actually grow plants very well because it is in a range that can be absorbed by the plant, while emmiter one would probably keep plants limping along, if they could even survive.
So when you are saying 450nm is that the same as 450 lumens because I have seen lumens abbreviated as lm and wanted to make sure I was reading the chart correctly.
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Old 01-19-2012, 02:02 PM   #14
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So when you are saying 450nm is that the same as 450 lumens because I have seen lumens abbreviated as lm and wanted to make sure I was reading the chart correctly.
Nothing in this thread has anything to do with lumens. A lumen is a measure of light visible to the human eye, and has little to nothing to do with plants. Nm is nanometers, and 450nm is the measure in nanometers between any two crests in that wavelength of light.

This should help:
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Old 06-16-2012, 05:53 AM   #15
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Originally Posted by samamorgan View Post
Not all spectrums are created equal!
Analyzing photosynthetically active radiation (PUR)

Please keep in mind that the following is purely informational, and should be taken very lightly if at all when considering an LED fixture purchase!

One of the reasons LEDs can be so much more efficient than T5, compact flourescent, and even metal halide is spectrum output. The chlorophyll pigment is green in color, which means that it reflects the green spectrum of light to our eyes so we see it as green. This means that it absorbs all other spectrums of visible light. Check out this graph:
Attachment 40237
As you can see, plants absorb visible light very well between ~400-500nm and ~650-700nm. The absorbtion rate drops off significantly in the green and yellow spectrums. Here are some LED emmiter comparisons in terms of specrum. Big thanks to redfishsc for doing the footwork on this. Notice that the warm white LEDs put out significantly lower blue spectrum spikes, but much higher red-yellow spectrum spikes. Essentially this tells us that cool white LEDs are almost always better for plant growth.

LEDs put out very specific spectrums of light, which are defined by the manufacturer. LED manufacturers can fine tune emmiters to put out exactly the spectrum specified by the client. Since PAR meters measure light between 400-700nm, an LED array putting out less par than a broad spectrum flourescent fixture may actually be putting out more photosynthetically usable radiation (PUR).

Why is this concept important?
Say two LED emmiters read around 100 PAR on a meter. The first LED spikes highest in the 550nm range. The second LED spikes highest in the 450nm range. So while both emmiters have the same PAR value, emmiter two would actually grow plants very well because it is in a range that can be absorbed by the plant, while emmiter one would probably keep plants limping along, if they could even survive.
So I get the importance of PAR ratings vs depth and all that, but I am still a bit confused.

It is my understanding that plants (and even corals) are best able to utilize yellow light (in the 65-10K area) yet corals show best color in the actinic 14-20K range and that's why those are the ranges most commonly used for corals. Right? And the whole watts per gallon thing gets thrown out the window when discussing LEDs, anyway. Right?

So my question is this: Regardless of PAR ratings (which seem to be ridiculously high in most cases because the lights are meant for reefs), aren't the vast majority of LED fixtures on the market relatively useless to the planted tank keeper because of the spectrum they put out? In other words, before taking PAR into consideration, shouldn't we be first looking at spectrum?

Sorry if we already went over this or if I am confusing the subject lol I am having trouble wrapping my head around it.

Joe
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