So I'm an Electrical Engineer by day, novice aquariest by night.
I've been thinking for weeks of something practical I could make at home that wouldn't cost exponentially more than just buying it pre-made off the shelf.
Then I had an epiphany! LED lights to grow plants! Genius!
So I went to my favorite parts supplier and lo and behold they did list kelvin ratings, awesome. So I searched for everything between 6000K and 7000K. Got lots of results. Perfect!
The question then becomes of intensity, and how on earth do you compare LEDs to incandescent (or even fluorescent) lights.
The brightest option was a 850 lumen LED at 6300K, 11.8W. Not bad at all. Now, if I look at a table of lumen's versus watts for incandescent lights that makes it equal to a 60W bulb (or 14W fluorescent). Does that make sense in my logic?
That's one heck of a lot of light coming from a single 12mm (half inch) diameter LED!
The issue, of course, is cost. These suckers cost $26 each! However, I was only looking at the top of the barrel. Lower intensity LEDs are of course less expensive and I'm sure I could find a more cost effective $/lumen. Still, a couple of those and it isn't going to be more expensive than buying a pre-made one (A 5 LED 19" @ 6500K marketed for growing plants is $136 and is only 12W).