You might want to take a look at the new T5 setups. The reflector and ballast are part of the unit. They are not horribly expensive. I am using two of them on a 15 gallon tank(48W) instead of the 2X65W PC fixture. It seems to be just as bright. However I have a Lux meter, so I should take a measurement.
Actually one hour later I took a measurement. The 24W T5 measured 30000 LUX at one inch. The 65W PC tube was the same. The PC tube has more hours on it. The cost of the replacement PC tube and the entire disposable T5 is about the same.
It looks like $ for $ you would be far ahead with the disposable T5's.