06-30-2005, 12:19 PM
Join Date: Jun 2005
nb - I'm certainly not a planted tank expert, but I do have some experience with led lighting systems (for house interiors).
It's great to see people experiementing with LED lighting for tanks. I believe they're the light source of the future for the aquarium.
There are a couple of issues with the white Luxeon LEDs though. Firstly, they're not all that efficient. They beat incandescent light bulbs, including halogens, but frankly don't come close to T5 fluorescents or HPS/MH. Then there's the light spectrum, which is not ideal for plant growth. The problem is that phosphor coatings for LEDs are not particularly advanced, compared to those used in off-the-shelf plant-grown T5 tubes (with good reflectors). This is compounded by the fact that white LEDs are optimised for reasonable colour rendition, not growing aquatic plants.
The solution is to use a combination of descrete colours (Luxeon offer a reasonable range of wavelengths) to create your own customised colour spectrum. Obviously some experimentation would be needed, but as LEDs are very easy to dim, it's within the scope of the DIYer.