Measurement of the absorption of light is complicated by the solvent used to extract it from plant material, which affects the values obtained,
- In diethyl ether, chlorophyll a has approximate absorbance maxima of 430 nm and 662 nm, while chlorophyll b has approximate maxima of 453 nm and 642 nm.
- The absorption peaks of chlorophyll a are at 665 nm and 465 nm. Chlorophyll a fluoresces at 673 nm (maximum) and 726 nm. The peak molar absorption coefficient of chlorophyll a exceeds 105 M−1 cm−1, which is among the highest for small-molecule organic compounds.
- In 90% acetone-water, the peak absorption wavelengths of chlorophyll a are 430 nm and 664 nm; peaks for chlorophyll b are 460 nm and 647 nm; peaks for chlorophyll c1 are 442 nm and 630 nm; peaks for chlorophyll c2 are 444 nm and 630 nm; peaks for chlorophyll d are 401 nm, 455 nm and 696 nm.
I was just going through doing some more research trying to find out why there are 2 different graphs then I re-read the wiki link again. I maybe the one wrong here since there are multiple answers. I am not sure now which one is the correct answer, if and how saltwater changes the spectral requirements of chlorophyll.
Their Photosynthetic Graph is off as it is for terrestrial plants which like that 660nm. If your Growing "Tomatoes" in you basement, this spectrum works quite well.
Zooanthellae Algae is what the coral need and the 660nm is blocked really quick in the ocean.
They have adapted with chlorophyll A & B one is more receptive to the 420-430nm and the other to the 460-470nm. They cross at 450-460nm. This is the sweet spot which feeds both.
The brightest Royal Blue or the Cool White with the best 450-460nm spike is your growth LED....
BTW 450nm pops the colours better than 460nm....
The only problem with 410-420nm LEDs is they are a lot less efficient than the Cree XT-E at 450-455nm.
That said the 410-420nm does bring out certain pigments in SPS and is worth having if you want ultimate looks.
So if I am understanding correctly, if we had more efficient 410-420nm LED's then those LED's would be better for growth than they are today and possibly better that CW and RB's if they were more efficient?
Cause from what I've read thus far happens to be true, corals prefer Chlorophyl A over B and Chlorophyl A spikes 420nm.
My current LED configuration is as follow
Same Driver Dimmable
8 Blue - Cree XPE
8 Royal Blue - Cree XPE
8 Cool White - Cree XPG
Non Dimmable Driver
4 Violet 410-420 - 3 Watt ???
Primarily SPS coral.