Which is provides the most light?

[Treebeard]

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?

[ImprezaSTi]

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

[mark]

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.

[spreerider]

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)