The hex tank was quite lovely with my single bright Marineland led strip, but it was definitely not bright enough to grow plants (not that these fuckers won’t just eat em all anyways but I want to try). Worse, the extreme depth of the tank means that in order to grow anything I need a very high lumen output. I priced out several options that would supposedly give me enough light – metal halide, halogen, power compact fluorescent, t5 ho, and all were ridiculous in their own way. MH and Halogen are expensive, hot, and eats electricity. T5 is great but there are not a lot of fixtures aimed at <20" width. Power compact would require a ludicrous number of bulbs to get enough light.
Then, I remembered my old issue with the track lights in the house. They all took $10 apiece 35 watt halogen spotlights. They were burning out 2-3 per room a month and getting real spendy to keep up. I took a big chance on some Chinese 4x1W LED replacement bulbs and they are AWESOME. Not one has failed in over a year of service and while the light is certainly very cold, they're bright as fuck.
So I tore down the old fluorescent hood fixture, drilled a piece of 3/4" aluminum flat to mount inside its housing, and then fitted four GU10 bases, each with a 110v 3x3W 6500k lamp. The result? Stunning bright light all the way to the gravel. Fish look brighter, plants (and algae) exploding with new growth. Once I build my new top, I plan on building a hex shaped 7 lamp fixture (which will allow me to grow anything I want to). I also ordered two 10w LED floods (also 6500k) for the 10 gallon. I'm totally sold on LED lighting, BTW.