Don't even think about incandescent light bulbs. The CFL power saver bulbs will work, but not very efficiently, and making a good reflector for them is very difficult. Their inefficiency as aquarium lights means using more wattage than otherwise needed, and having even more need for a cooling fan. If you have a Radio Shack near you, they have a few cooling fans that can be used. For a 12 volt D.C. fan, also buy a variable 12 volt DC power supply - a transformer/rectifier assembly that lets you chose to run the fan at 12 volts, 10 volts or even lower. Using the lower voltage makes the fan run quiet.