Have you seen this article?

[saltyfilmfolks]

Hi Mike. Ive read up on your lights quite a bit. If I may say its real science not much B S .

Hit 420nm, 447nm, 495nm with a little 660nm and you're good to go. The rest is aesthetics

When I say this, people say Im nuts.

Nerds Rule!!!!

 

[TheEngineer]

So how much Chlorophyll B is in most chloroplast with in the zooxanthalae in our corals? If your chasing B you'll be chasing it a long time. Clade C is present instead, however density of population is low in corals (though higher in clams) so chasing its peak yields minimum ROI. In fact hitting the cartenoid peredinin has more effect at the 490-495nm wavelength than going after chlorophyll C. Folks post the absorption chart often yet fail to factor in density of each Clade of Chlorophyll, not to mention Chlorophyll B is not present in the coral's dinoflagellates. Hit 420nm, 447nm, 495nm with a little 660nm and you're good to go. The rest is aesthetics. There are secondary, third and forth absorption points for Chlorophyll A, B and the cartenoids but again ROI is minimal.

I feel like I am missing something from your post. Chlorophyll a and peredinin make up 80% of the zooanthella pigments. Add Chlorophyll c and you're up to 93%. The wavelengths you listed are for Chlorophyll a (420nm), Chlorophyll b (447nm), one of the peredinin points (495nm) and the second absorption point of Chlorophyll a (660nm). All of which are in the chart I posted. Who talked about chasing Chlorophyll b? Was it in the reference article?

 

[SB Reef Lights]

You are almost certainly correct that higher end LEDs will be less susceptible to these variations. However, if we look to chromaticity as you have provided, you must consider this specifically in the wavelengths that are of importance to corals, particularly in the 400-500nm range (give or take). The spacing between these colors is quite small. You can see in the chart below how quickly the absorption drops off for both Chlorophyll a and b. Missing the mark by 5nm is quite severe in terms of efficiency.

Temperature, as shown in your second image, is a huge factor of course. Especially over the LED lifetime.

I feel like I am missing something from your post. Chlorophyll a and peredinin make up 80% of the zooanthella pigments. Add Chlorophyll c and you're up to 93%. The wavelengths you listed are for Chlorophyll a (420nm), Chlorophyll b (447nm), one of the peredinin points (495nm) and the second absorption point of Chlorophyll a (660nm). All of which are in the chart I posted. Who talked about chasing Chlorophyll b? Was it in the reference article?

The article posted this graph along with references Chlorophyll B. That was all. 447nm is the peak point for Chlorophyll C, though some put it at 450nm. Close enough. Hitting 447 to 455nm hits the primary points for both Chlorophyll C and Peridinin. Hitting 490nm and 660nm hits the secondary points for Chlorophyl A and Peridinin. Hitting 395nm would hit the secondary point for Chlorophyll C, however the ROI would not be there to add lots of 395nm diodes, especially since diode life on sub 400nm is so short.

 

[TheEngineer]

Ah! It was in the article I was trying to figure out what I missed. Thanks for those details.

 

[fragit]

Wow I didn't realize that when I posted this article it would invoke such an in depth conversation. Thanks to all for participating. I'm planning a build and have been researching lights and came across the article. Honestly there is so much conflicting information out there it's difficult to come to a decision.

 

[dacianb]

Wow I didn't realize that when I posted this article it would invoke such an in depth conversation. Thanks to all for participating. I'm planning a build and have been researching lights and came across the article. Honestly there is so much conflicting information out there it's difficult to come to a decision.

Will be a world wide holiday when all reefers will have same oppinion on led lights [emoji1] [emoji1]

 

[dacianb]

In the end, what I understood is that 430-475 nm range have to be covered with a peak of 450nm. This means violet-deep blue - regular blue. Anything else is for look.