Which ballast should I get?

[Myka]

Of you want the highest output possible, then go with the PFO HQI ballast to run a european mogul bulb. The bluer the light the less intensity you will get though. It's better to run 10K with some strong actinics, than 14 or 20K with no actinics.

Google "Sanjay reef lighting", and check out that page. It compares the output (PPFD) of many different ballast and bulb options.