Wrong, Halides are more efficient than Fluorescent bulbs. The heat in a
halide is more concentrated
so it seems more inefficient, but it's not.

jb

"Robert Cadieux" wrote in message
...

"david" wrote in message
nk.net...
I am about three months into starting my first reef tank. It is 120
gallons
and I am using an aquaspacelight with (2) 250W metal Halide bulbs and
(2)
24W Blue lights. I have noticed that these lights along with all the
pumps
etc. have almost doubled ny electric bill. Are VHOs any more
efficient.
In otherwords does anybody know whether it would require the same amount
of
electricty to produce 500 watts of light regardless of whether it is VHO
or
metal halide.


500 watts is the amount of electricity, or power to be more specific, that
the bulbs are consuming to produce light. What you really want is light
output or intensity, usually measured in lumes, lux or candles. As a
comparison you're asking for a car that attain the speed of 10 MPG when
you
really want to know how fast the car goes and you should be asking how
many
miles per hour it can go. Generally speaking fluorescents, such as T8, T5
and VHO bulbs are somewhat more efficient than metal halide and much more
efficient than traditionnal incadescent bulbs. But the lighting is
different with fluorescents. The light is more difuse and you don't get
that shimmering effect you get with MH.

Two things you may consider. Using a combination of fluorescents and MH.
Keep half of the MH running, 250W, for about 4-5 hours a day and replace
the
other with about 125 watts of actinic and T5 fluorescent lighting. That
way
your peak consumption will be 375 watts for 4-5 hours and down to 125 for
the rest. Most corals do fine with this combination.

The other is that MH give off lots of heat. This may very well offset
your
heating costs in the winter which means your electric bill will only
really
be higher during the summer.

Robert