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Re: Metal Halide advice needed

Chester asks about metal halide lighting.
- You have to buy a ballast that is matched for a bulb. Which bulb
manufacturer makes really good bulbs?
The January edition of Aquarium Frontiers Online has an article that
investigates the performance of several 250 watt metal halide lamps.  It
appears that the Iwasaki 6500K lamp is a good contender for our needs. An
additional issue to keep in mind is that not every manufacturer makes a good
selection of lamp color temperatures in every wattage.  Iwasaki doesn't make
a 6500K lamp in 175 watts for example. I found the 5000K and 5500K lamps to
be too yellow, so the only choices for my tank (65 gallon) in 6500K were the
Coralife 175 watt or the Iwasaki 250 watt. Calculate the number of watts
needed at around 3 watts/gallon to determine the wattage required and then
decide if you want the total in one lamp or more. 
 - Should I go with an electronic or conventional ballast?
I had no luck with the IceCap electronic ballast.  I bought a coil/capacitor
ballast for about $60 from a local electric supply house and it works fine.
It does make a hum and produces some heat.
 - DIY?
By far the cheapest way to go.  The ballasts for the 175 watt and 250 watt
lamps are about $60, the 175 watt lamps are about $80 while the 250 watt
lamps are about $60.
 - Mass produced? 
Not worth the expense, IMHO.
- Hanging pendants or suspended fixture of sorts.
Depends on the size of the tank and your own preference for how it looks.
 - How about reflectors if I go with DIY? Flat polished aluminum or one of
those "Spider" reflectors? How good are they anyway? I would want a fixture
that was somewhat tall (~ 1 foot or so) so that you couldn't really see the
bulb and the reflector really aims to light downwards... 
I have a Spider reflector inside a built-in cabinet and I am satisfied with
the way it works. I doubt I could get a local sheet metal shop to make all
those bends for any less than the cost of the finished reflector, plus it
came with the mogul base.  Most metal halide lamps are made to be operated
best in the vertical position. Mine is horizontal and seems to be okay. A
pendant allows an open tank but will spill light out into the room.  A
closed hood provides the "look" that I like, it's your preference. IMHO,