Technical Lighting Question

[wschoenfeld]

I am interested in making a reef aquarium light source out of LEDs. This will allow me to choose the specific spectral emission. I am interested in finding out the particular parts (wavelengths) of the lighting spectrum that are beneficial and those that are unwanted. In other words, if you could choose the wavelengths between 390 - 650nm that you wanted for your reef aquarium, which would you remove, and which would you keep? If anyone has knowledge in this area, I would highly appreciate your comments.

 

[Chucker]

You might want to look at these past threads on the subject-

http://reefs.org/phpBB2/viewtopic.php?t ... leds+diode
http://reefs.org/phpBB2/viewtopic.php?t ... leds+diode
http://reefs.org/phpBB2/viewtopic.php?t ... leds+diode

 

[pcmankey]

Research the chlorophyll absorption spectrum and go from there.

 

[buff1]

I actually bought a strip light with 24 LEDs to supplement my 2x55 watt power compacts. I turn the Leds on an hour before the main lights come on and leave them on an extra two hours at night. The strip is thin enough to fit right between the reflectors for the pc's. There is enough light output from the LED strip that it looks like I have one of those old 25watt incandescents that you would get with a 10 gallon aquarium. The biggest problem that you're going to have is that there isn't an established solution for this application of LED's. You can be the guinea pig! The most interesting link I have seen is this one. http://netdisty.net/ds/r30-123/. I would guess that you would need quite a few of these to approach the lumen output of metal halide, but the reward would be much lower power usage and not having to replace the bulbs every year. I would love to see Sanjay do a report on this subject. My personal feeling is that this could easily be a viable source of lighting in a few years (ie: cost comes down and efficiency/intensity goes up). Good luck to you and report back any discoveries you make!

 

[buff1]

You might be able to get away with fewer LED because there would be less wasted light. Even with reflectors, MH and flourescents can't really be pinpointed. LEDs come with various dispersion angles. You could choose the tightest beem and point it directly at a specific area of the tank. Virtually all the light would be concentrated in a relatively small area. Just another thought on the subject.