there is a million t5 bulbs ou there... aqua science german bulbs are amazing and there are about 8 diff color spectrums online at thatpetplace.com or doctor fosters.
i personally used t6, t5, vho, pc... i like t5 the best if its a 4 bulb unit because you can have a wide spectrum of light, 4 bulbs with 4 diff spectrums. this makes your fish glow. others are good as well. i think power compact has the least choice with choosing color spectrum; plant growth bulb, 2 diff color artinics, a 10k and a 12k. t6 and vho have wide selection of bulbs and then there is always metal halide which is great but pricey to run if you have a large tank.