Which is provides the most light?
 

I do not fully understand lighting concepts. I currently have 2 - 96 watt power compacts. (96W 10000K Bulb and 96W Actinic Bulb). My math tells me that this equals a total of 192 watts. Is this not more light then a single 150 watt MH bulb? But research tells me that MH is "better" than PC....am I missing something?

You cannot use watts to compare MH vs PC. Watts is generally used for comparing T5 and MH.

You can use watts for comparing any type of bulb but look into PAR/watt or lux/watt. Basically, MH gives more light energy per watt or is more efficient.

watts is how much electrical power is used and lux is how much light is put out from the source,
lux/w is how efficient the light is, MH have the highest Lux/Watt of any light except sodium lamps but they are yelllow so of no use in aquaria (street lamps)