you might find this interesting

drdsanders · 07-14-2006, 11:37 AM

from what ive been researching, lumens are more important than wattage.
Heres a lumen per watt scale on different bulb types
(this info was supplied by a garden supply company. Theres always the chance its incorrect)

T12 flourescent......65 lumens per watt
T8 flourescent........81 LPW
Halide/HQI............80 LPW
T5 flourescent........92 LPW

i couldnt find lumen output on power compact flourescents.

reiple · 07-15-2006, 10:39 PM

it is. nice info. too bad you dont have the PC lumen per watt.

Geoff · 07-15-2006, 11:56 PM

those look correct. this also shows the differences between a point source and an indirect source. the lumens are rated for the entire bulb. a MH is a point source so those lumens are all coming from a single point. this is why they penetrate deeper water so well. flourescents have the light coming out over their entire surface. more of the light is absorbed by the water. not able to penetrate as well.

G~