I have used T-8's (HO) driven by an older Motorola design electronic ballast that is not made any more, that I can tell (they were sold to Osram a few years ago). I bought 8 of them, using 6 banks with 2 spares. The ballast has a ballast factor of 128 which overdrives the bulbs. I have used Phillips 5000k bulbs which have a CRI of 98 so they look good to me, in combo. with sylvania actinics and some Lumichrome 6500k bulbs (95 CRI). Two of each. I use a total of 6 banks, and can simulate sunrise/sunset over a 3 hour period using timers. The fish seem to appreciate waking up to only one bank of actinics, I think.

To compensate for the lack of intensity/rapid diffusion of light pattern, I incorporated some metallized parabolic eggcrate with a thin piece of acrylic super glued to that to filter any uv, all mounted to the hood and sealed around the edges with rubber tape. I put a couple of muffin fans in the hood for cooling. I get glimmer lines, but nothing like MH bulbs of course. It gives me a color temp. of around 7000k by my rough approximation, with a high CRI so it is easy on the eyes, and the colors really jump out. I have had no sps, just lps and softies and they do real well. I have had the bulbs on a rotation of around 12 mo., but where I don't change them all at once. I think that it is probably not good to go from low to high (new) intensity all at once.

I am looking for something in a T-5 that will be close to this set-up. The above design has served me well, but I would like to incorporate some of this design on another tank using the more compact T-5's with SPS and see how it works. I tried to find T-5 for a 10 gal. nano set-up but they don't seem to exist in an HO form factor. Any ideas?