you might have better luck in the equipment section.
if you are a handy person, who knows some basic electrical stuff, you can fairly easily wire up either vho or pc bulbs to a ballast, if you are a little tool shy, there are a number of companies selling lighting kits for both of these options. do you have a canopy for your 45, or is the only thing on the top the light and some glass? if you have an actual canopy, you will want to start researching "retrofit" kits for both vho and pc in whatever the length of your tank is, these are easily screwed into the canopy and simply plugged in. if you do not have3 a canopy, you are pretty much stuck with complete vho or pc light fixtures, unless you decide to go the canopy route.