I don't have personal experience, so take my comments for what they are worth...
I agree with Epic, 3 LEDs will lead to very focused areas of light. I understand the ripple thing, but keep in mind you are comparing 150W HQI bulbs to tiny 3W LED emitters.
When you balance between the output and number of LEDs, lots of low power LEDs are no good, but too few spotlight might not be good either. Rather than 3 triple LEDs, I'd do 9 (or 12) single emitters. When you go from 1 Watt to 3 Watt you can see the brightness triple, but going from 3 Watt to 3x3 Watt doesn't do that.
Check out Cree/Seoul Semiconductor LEDs. LED technology is advancing rapidly, and what was the best yesterday could be replaced by less expensive, more efficient things today.
Adding a lens to a LED to bundle the light sounds weird to me. Add a reflector, sure, but LEDs have a directional light output already, and adding a lens IMO just reduces light output further.
If you add distance between the LEDs and the water surface, keep in mind that the inverse square law darkens things rather quickly.
And finally, for $150 you can build yourself the awesomest, brightest T5 setup you can imagine. But of course that isn't as exciting.
(Just subscribing to your thread).
|