Question about the watts per gallon formula

[InfernoST]

When the recommendation of say 3-6 watts per gallon are calculated is the resulting wattage as in incandescent (true) wattage or fluorescent wattage? I ask this because a 16 watt fluorescent bulb's output is equal to a 60 watt incandescent lamp. There is huge difference between a 54 watt fluorescent and a 50 watt incandescent lamp.