Coral Coloration Glossary

You're welcome. This chart is a few years old, I think, so I wonder if there might be one that has more excitation/emission spectra represented.
Ralph.
The data came from Dana's articles on Advancedaquarist.com. There are two sets of articles, the first being the Feature Article: Coral Coloration: Fluorescence: Part 1, and the other being Feature Article: How to Make Corals Colorful (multi-part article). I cited the sources when I first posted the slides on a couple of reef-keeping sites. Regardless, I wouldn't recommend putting too much effort into trying to excite blue-violet to violet pigments. Most people wouldn't notice them, anyway, even if you blasted them with broad spectrum violet/UV light. As far as timeliness of the data, I wouldn't imagine anything could be done to improve upon Dana's articles.

One thing I did notice in the data was that the excitation wavelengths were very specific. Dana, if 450nm was the excitation wavelength, would a purely monochromatic 453nm emitter have any effect? Assuming you did need a very specific wavelength to excite each pigment, you'd need an impressive range of LEDs to cover them all, since each colored LED typically has a fairly narrow emission range. I did manage to find sources of LEDs to provide what I thought was sufficient wavelength overlap at the half-power region of each emitter, but don't have the coral population sufficient to prove that I succeeded. Right now my non-white LEDs range from 390nm through 520nm.
Dan
 
Oh, that originally was your data, then. The reference to Dan came from this article by Dmitry and Vahe:

http://www.advancedaquarist.com/2012/10/aafeature
Yes it was, and despite my insistence to cite Dana as my source, they somehow left his name out of the reference. The sources were Dana's articles--which were fantastic.

I had originally posted them on RC, which is where Dmitry and Vahe discovered them.
 
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Thanks Dan. I really like the way you presented the excitation/emission spectra. Wish I had thought of it myself. Excitation bandwidths, like those of emissions, are fairly broad. I'd like to look at FWHM, but any blue LED should be a suitable excitation source (if blue does the trick to begin with.) The difference would be in the brightness, or quantum yield, of the emission.
 
The data came from Dana's articles on Advancedaquarist.com. There are two sets of articles, the first being the Feature Article: Coral Coloration: Fluorescence: Part 1, and the other being Feature Article: How to Make Corals Colorful (multi-part article). I cited the sources when I first posted the slides on a couple of reef-keeping sites. Regardless, I wouldn't recommend putting too much effort into trying to excite blue-violet to violet pigments. Most people wouldn't notice them, anyway, even if you blasted them with broad spectrum violet/UV light. As far as timeliness of the data, I wouldn't imagine anything could be done to improve upon Dana's articles.

One thing I did notice in the data was that the excitation wavelengths were very specific. Dana, if 450nm was the excitation wavelength, would a purely monochromatic 453nm emitter have any effect? Assuming you did need a very specific wavelength to excite each pigment, you'd need an impressive range of LEDs to cover them all, since each colored LED typically has a fairly narrow emission range. I did manage to find sources of LEDs to provide what I thought was sufficient wavelength overlap at the half-power region of each emitter, but don't have the coral population sufficient to prove that I succeeded. Right now my non-white LEDs range from 390nm through 520nm.
Dan

Thank you for clearing that up. With the wide spread of information across the Internet it can be a challenge to keep credits in line (as we can see here).

Ralph.
 
Thanks Dan. I really like the way you presented the excitation/emission spectra. Wish I had thought of it myself. Excitation bandwidths, like those of emissions, are fairly broad. I'd like to look at FWHM, but any blue LED should be a suitable excitation source (if blue does the trick to begin with.) The difference would be in the brightness, or quantum yield, of the emission.

I have to agree that the chart is really helpful, especially of great benfit when creating an LED array. Thanks to Dan for coming up with this!

Dana - Do you know the excitation spectra for the Red Fluorescent Proteins? (I don't see them on the chart). This seems to be the only coloration that is a challenge for my LED array (red in Acans turns to a more reddish-orange, for example).

Ralph.
 
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Thanks Dan. I really like the way you presented the excitation/emission spectra. Wish I had thought of it myself. Excitation bandwidths, like those of emissions, are fairly broad. I'd like to look at FWHM, but any blue LED should be a suitable excitation source (if blue does the trick to begin with.) The difference would be in the brightness, or quantum yield, of the emission.
 
I have to agree that the chart is really helpful, especially of great benfit when creating an LED array. Thanks to Dan for coming up with this!

Dana - Do you know the excitation spectra for the Red Fluorescent Proteins? (I don't see them on the chart). This seems to be the only coloration that is a challenge for my LED array (red in Acans turns to a more reddish-orange, for example).

Ralph.
.
Here you are. None of these have secondary or tertiary emissions or excitations.
upload_2017-7-14_14-28-34.png


upload_2017-7-14_14-22-27.png
 
.
Here you are. None of these have secondary or tertiary emissions or excitations.

Thank you, Dana, that is very helpful. Typically, reds are easily kept under good t5 lighting, so perhaps a bit more green-yellow to yellow spectrun might help out here.

Ralph.
 
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It was a simple Excel table-to-graph, with some manipulation of the graphic colors. I've been wanting to add any other data sources and graph it again.
I've found that there's a significant difference in intensity and emission spectra between each set of violet and blue LED wavelengths. I've got each set on a different string, so I can play with the intensity settings. Interesting results with the UVs.
 
It was a simple Excel table-to-graph, with some manipulation of the graphic colors. I've been wanting to add any other data sources and graph it again.
I've found that there's a significant difference in intensity and emission spectra between each set of violet and blue LED wavelengths. I've got each set on a different string, so I can play with the intensity settings. Interesting results with the UVs.

I've also done some separating of the channels for violet (403 nm)/hyper violet (428 nm) and royal blue (450 nm)/blue (475 nm). I also have Cyan (495 nm) on a separate channel and I've found this hue increases alkalinity and calcium usage more than what I expected. I even have a deep red (660 nm) channel...which some may find distressing ;)
 
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Dan,
It looks like you've hit upon something I've suspected for quite a while - that a bandwidth outside of the chlorophyll a, b, and c absorption spectra often used by hobbyists to judge photosynthetic response can be quite useful (due to the accessory pigment peridinin.) I began thinking this when PFO Lighting sent me a LED prototype that would be marketed as Solaris - it generated a lot of blue-green light but not a lot of PAR, yet corals that many considered intolerant of low light were growing very well (and a Pocillopora damicornis was spawning.) I've got an experimental protocol established for investigation of spectra, just need to get the lab going... Great observation. In my opinion, you might want to consider publishing your data!
 
Dan,
It looks like you've hit upon something I've suspected for quite a while - that a bandwidth outside of the chlorophyll a, b, and c absorption spectra often used by hobbyists to judge photosynthetic response can be quite useful (due to the accessory pigment peridinin.) I began thinking this when PFO Lighting sent me a LED prototype that would be marketed as Solaris - it generated a lot of blue-green light but not a lot of PAR, yet corals that many considered intolerant of low light were growing very well (and a Pocillopora damicornis was spawning.) I've got an experimental protocol established for investigation of spectra, just need to get the lab going... Great observation. In my opinion, you might want to consider publishing your data!

Dana,
As you know, the data's not mine, but I do have some slides I created based on others' data you might like. I'll send you a link.
 
Dana, please check your email.
Dan, Got the email. Thanks! I'll take a close look tomorrow. too tired tonight - worked on getting the new lab's sheet rock in, primed and painted. Tomorrow, suspended ceiling install and setting cabinets!
 
Very timely stuff, since I was asked about fluorescent proteins just two days ago, by a visitor to our local Public Aquarium. Thanks for taking the time to distill and share this info!

~Bruce
 

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