Yes watts is the meaasurment of the amount of electricity
it uses, and yes it is in direct corilation of how much
heat is produced, but since watts is the amount of energy
it will give off, watts makes a good measure, but the
spectrum it gives off is important to look at. You want a
quality bulb that gives off energy in the right spectrums.
All of your aquarium bulbs give a spectrograph of what
light it gives off. And all light spectrums prouduce heat.
when light is absorbed, heat is given off. And of course
there is waisted entergy given off as heat directly from
the bulbs and the balast.

The problem with Lumens is that it is a measurment of how
much light the eye can see. This falls short with what is
considered beneficial to the corals. For example a sodium
light produces a lot of lumens, but is too yellow for a
reef tank.

Wayne Sallee


erik wrote:
Wait a minute!
Light intensity is not measured in watts! That's the whole point of
Tim's question. Leave "watts per gallon" as a heater spec. Light
intensity is measured in lumens, or foot candles, or candellas etc...

Tim,
Sorry I don't have a direct answer to your question but it is a good
question. (worthy of a good answer) I think you may have to contact
the lamp manufacturer to find out what the actual light output for
each lamp is. The wattage spec is the amount of electricity it uses,
not necessarily how much light it produces.

On Thu, 22 Sep 2005 23:47:12 GMT, Wayne Sallee
wrote:


Don't worry so much about those numbers, but look at the
actual spectrum. Figure wats of light per gallon. You want
3 to 5 wats per gallon. 3 being low, 5 being where you
want to be for stonys,and even higher like 6.6 is good.
And metal halide is the best light.

Wayne Sallee
Wayne's Pets



Timcat wrote:

I have a puzzling question. In researching lights to set up a new tank, I
can't find anything relating Fluorescent tube wattage and MH wattage to
lumens, or a comparison to incandescent...like you always see on CF tubes
for home lighting, i.e. 20W CF equals a 100W incandescent bulb. I'm
wondering if, for example, 500W of CF lighting has the same output as 500W
of MH. Am I making this clear? Am I talking apples and oranges here, or am I
missing something?

Tim