Selection of LEDs

I want to share some thoughts on LED selection. In return, I would like you to bounce your thoughts off of mine and hopefully in turn, we can narrow in on the right spectral combination for my needs. I am in the process of selecting the right combination of LEDs for my SPS reef aquarium. I have been given some tips from others in another thread, and I truly appreciate it.

Let's look at white LEDs first. We have 3 options available to us. We have the Cool White (5,000-8,300 K), Neutral White (3,700-5,000 K) and Warm White (2,600-3,700 K) diodes it's commonly believed that photo synthesis strongly favors a color temperature of 6,500 K. So with that in mind, cool white appears to be the best option for white light LEDs.

With color LEDs, I want to look at this spectral graph showing the absorption rate of light for stony corals at particular wavelengths.




As you can see, there are spikes between 450-500 nm, with a rise in absorption rate beginning around 400 nm and decline ending between 500-550nm. There is also a spike at about 670, with a rise in absorption rate beginning around 650 nm.

With these spike in mind, let's look at the colors that favor these spikes:

Violet- 410-420 nm
Royal Blue- 450-465 nm
Cool Blue- 465-485 nm
Cyan- 490-520 nm
Deep Red- 650-670 nm

The majority of the peaks occur in the Royal Blue wave length, which to me, would make this the most important and most numerous diode in unit. All four of the above diodes occur where the majority of the spike occurs on the shorter end of the wave length spectrum. To me, all 4 colored diodes would be important to achieving a complete spectrum.

The other peak at about 670, with a rise in absorption rate beginning around 650 nm, is similar in the range of the Deep Red diode, also making this wave length important.

 

With all that in mind, This is what I am looking at over my 20 gallon:

 

Subscribed. Really interested to see what the "best combo" would be. You're looking for the best for sps only, correct? No lps or softies in the tank? Also, I thought too much red promoted growth of some kind of red algae?

I hope you get the answers you're looking for!

 

Well, my tank is predominately SPS, but those absorption rates are typical for coral and probably for most plants as well. Red appears to provide a necessary peak for chlorophyll A, which is found in plants/algae.

 

Lighting spectra, Photosynthesis, and You (new plots!) - Lighting Forum - Nano-Reef.com Forums

 

Yep. I saw that link earlier after I posted this. I actually asked a couple questions in it.