LED Spectrum Peaks - is it possible to speculate?

spideybry

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Lately, I've found myself doing a deep dive back into reef lighting. I've been out of the hobby for a few years and now that I am coming back - I realize there are a bunch of new pieces of equipment and there are a lot of budget brands.

The setup I purchased came with a light. Initially I was going to go with something that was tried and true to keep a reef, but figured why not see what this light could do. Since this light came from a brand that was unknown/not fully trusted and lacking specific information that would say if these lights effective at keeping a thriving reef tank, I want to know if it is possible speculate with any certainty if the unit will hit those peaks in the spectrum that are proven to keep corals.

Many of the better brands include a spectral analysis that show off exactly how a light will hit those peaks.

1599415112760.png


So, what I am wondering is - if a light lists:
  • Channel 1(11pcs): 11pcs 20000k Cool White
  • Channel 2(55pcs): 44pcs 420nm Moon Blue,11pcs 520nm Green
  • Channel 3(11pcs): 11pcs 470nm blue
  • Channel 4(35pcs): 18pcs 4500k Natural White, 11pcs 450nm Royal Blue,6pcs Growth Red

Would this be a fair representation of what the spectral analysis would look like?

1599415139323.png


I guess LED count and intensity factor into this as well so it is uncertain on that end... So thoughts? Is this an okay way of avoiding a spectrometer with a budget light system?
 

Spare time

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Corals contain ch A and ch C2 in ther zooxanthellae as well as a mix of other photopigments. I can find some more spectral charts later when I get home.
 

Spare time

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Reefs.com mentions that common photopigments in zooxanthellae are chlorophyll a, chlorophyll c², peridinin, and -carotene. Wiki also mentions diadinoxanthin.

If you need me to get the peak sensitivity wavelengths lemme know. I found several graphs but usually the peak pops up on google when searched.
 
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spideybry

spideybry

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Do you have a link to the light?
I am curious going beyond this light btw, but here is the link to the one I have:

I have another thread where I am measuring the PAR on the light as well if you’re curious:
 
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spideybry

spideybry

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Have you seen this article by @Dana Riddle? There might be an inexpensive way to evaluate your hypothesis of PAR value estimates.
I haven’t but it looks like a solid read. Thanks, I’ll be reading now. I already have a PAR meter until Wednesday at least lol (rented from BRS).
 

Nano sapiens

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Fascinating subject that can get quite involved...

If you really want to have some fun with your lighting you can actually build a simple spectrometer:

https://store.publiclab.org/collections/spectrometry

When building my LED array many years back, I built and used one of these. Can't vouch for accuracy since I don't have access to a professional spectrometer, but based on the LEDs I used it seemed to be 'in the ballpark' at least and my corals were/are just fine with the outcome. Would love to have Dana build one and see how it stacks up to his lab equipment :)

Dana's articles are all great. Here is another great article with a whole lot of lighting information all in one place:

https://reefs.com/magazine/light-in-the-reef-aquaria/
 
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spideybry

spideybry

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Fascinating subject that can get quite involved...

If you really want to have some fun with your lighting you can actually build a simple spectrometer:

https://store.publiclab.org/collections/spectrometry

When building my LED array many years back, I built and used one of these. Can't vouch for accuracy since I don't have access to a professional spectrometer, but based on the LEDs I used it seemed to be 'in the ballpark' at least and my corals were/are just fine with the outcome. Would love to have Dana build one and see how it stacks up to his lab equipment :)

Dana's articles are all great. Here is another great article with a whole lot of lighting information all in one place:

https://reefs.com/magazine/light-in-the-reef-aquaria/
Thanks, these are some great links as well. Do you have your results anywhere? I am curious to see how they look.

I may pick up the webcam kit and try to design and 3d print some sort enclosure. Seems like a fun little gadget.
 
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spideybry

spideybry

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Reefs.com mentions that common photopigments in zooxanthellae are chlorophyll a, chlorophyll c², peridinin, and -carotene. Wiki also mentions diadinoxanthin.

If you need me to get the peak sensitivity wavelengths lemme know. I found several graphs but usually the peak pops up on google when searched.
Also, I’ll take what I can get - if you find them I’d appreciate it. Just trying to absorb info at this point and make some observations.
 

Spare time

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1599443326846.png
 

Spare time

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The numbers are easy to google if you want the exact peaks. Just look up absorption spectrum of x
 

Nano sapiens

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Thanks, these are some great links as well. Do you have your results anywhere? I am curious to see how they look.

I may pick up the webcam kit and try to design and 3d print some sort enclosure. Seems like a fun little gadget.
This was a SPECTRA approximation based on the particular LEDs in the array and their respective intensities:

12g PWM DIY 97%_022116.JPG
 
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spideybry

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This was a SPECTRA approximation based on the particular LEDs in the array and their respective intensities:

12g PWM DIY 97%_022116.JPG
That’s a great looking spectrum analysis, I just wonder how accurate it is. Based of this I will be trying the DIY spectrometer. Do you have any coral shots that you could share?

The article you linked was amazing, really lit a light bulb or two in my head lol. The idea that different chromoproteins floresce under different wavelengths makes so much more sense now.

Also, the idea that most of the photosynthesis happens around the 400-480nm range makes me inclined to believe that people are running tanks with full attinic LEDs - hitting specific wavelengths in that range - similar to the 20000k metal halides that were more popular when I was in the hobby.

Do most LED tanks look like full blue attinic blow out for most of their photo period now?
 

blasterman

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The reason we run blue heavy tanks with LED is because we have the ability to do so. With discrete channels to adjust running 450nm many reefers like the pop that 450nm provides. That was tricky to do back in the halide and tube days. Now you can just turn up the blues with a dial or an on your phone.

This has been beaten to death, but theres no evidence 400-440nm violets do anything better than the common 450nm band that is universal to all types of reef lights including LED , halide and T5. Some of the most legendary halide bulbs made for reefing have trivial amounts of 400-440nm but they've grown spectacular SPS tanks over the years. Anybody can write articles on in vitro chlorophyll absorption ratios but ask them to show show their side by side SPS tanks and how the one with violet is growing better and they shut up because it doesn't exist.

Don't buy into the violet nonsense. Most of the mainstream lights have them anyways. Base your choice on features and coverage.
 

Nano sapiens

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That’s a great looking spectrum analysis, I just wonder how accurate it is. Based of this I will be trying the DIY spectrometer. Do you have any coral shots that you could share?

The article you linked was amazing, really lit a light bulb or two in my head lol. The idea that different chromoproteins floresce under different wavelengths makes so much more sense now.

Also, the idea that most of the photosynthesis happens around the 400-480nm range makes me inclined to believe that people are running tanks with full attinic LEDs - hitting specific wavelengths in that range - similar to the 20000k metal halides that were more popular when I was in the hobby.

Do most LED tanks look like full blue attinic blow out for most of their photo period now?
For those who want to see coral non-fluorescent as well as fluorescent pigments, the general rule of thumb with LED arrays is make sure you have sufficient 'actinic' for photosynthesis...and then tweak the white/other colors to your viewing preference. For those interested in just the 'black-light poster' look, a very strong actinic with minimal white/other colors works, too.

I've been experimenting with a touch less 'white' and more 'cyan' than I typically run lately and the corals/false corals are most fine with it :)

12g FTS_080720.jpg

12g Left 2_080720.jpg


12g Right 1_080720.jpg



This is the spectrum graph from the DIY spectrometer program:

12g LED Array (Stunners + 75% DIY) 122813.png


Small 12g tank, so I was running a bunch of Stunner Strips in addition to DIY LED strips at the time. Gives you an idea of the output format.

Just in case you weren't aware, there is an 'Aquarium Lighting Forum' here on R2R (run by Dana Riddle) with lots of great info:

https://www.reef2reef.com/forums/aquarium-lighting-by-dana-riddle.956/
 
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Dana Riddle

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Fascinating subject that can get quite involved...

If you really want to have some fun with your lighting you can actually build a simple spectrometer:

https://store.publiclab.org/collections/spectrometry

When building my LED array many years back, I built and used one of these. Can't vouch for accuracy since I don't have access to a professional spectrometer, but based on the LEDs I used it seemed to be 'in the ballpark' at least and my corals were/are just fine with the outcome. Would love to have Dana build one and see how it stacks up to his lab equipment :)

Dana's articles are all great. Here is another great article with a whole lot of lighting information all in one place:

https://reefs.com/magazine/light-in-the-reef-aquaria/
I haven’t but it looks like a solid read. Thanks, I’ll be reading now. I already have a PAR meter until Wednesday at least lol (rented from BRS).
Post PAR numbers when you get a chance. Need to know model # (MQ-510, etc.), sensor color (blue or white) and if measurements were in air or water.
 

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