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lighting dilemma



Here's my quandary:  Should I go with compact fluorescents or T8's?

I'm upgrading the lighting on my 29 gallon planted tank.  The tank
footprint is 30"x12" and it is currently lit by a measly 40 watts (2 24"
T12 tubes).  I'd like to get some opinions on which of the following two
upgrade options sounds best:

option 1:  4 24" 17 Watt T8s with a rapid start ballast (total of 68
Watts).  Ballast runs about $45, and each tube is about $8.

option 2:  2 22.5" 40 Watt Compact Fluorescents (High Lumen Biax bulbs from
GE, page 942 of the '96 Grainger catalog).  This ballast is also rapid
start, and runs about $33, and the tubes are about $15 each.  Total wattage
= 80.

As you can see, the second option is slightly cheaper, and provides MORE
POWER (I can sense Tim Taylor's grunting from here).  Lumen's per watt
ratio and average lifetimes are very similar for both types of bulbs, so
there really is a cost advantage for the second option.  But I wonder if
spacing 4 lower power tubes over the entire tank would be better than two
high power tubes generating more concentrated light.  I guess it's just a
matter of opinion, so I'd like to get yours.

Additional tank info:  KH = 2-3, pH=6.4-6.6, yeast CO2, Fluorish fertilizer
+ supplemental K2SO4 and KNO3 with weekly water changes.

Anyone looking for info on compact fluorescents please feel free to e-mail
me directly.  Lamp holders for the high lumen biax lamps are a tricky item.

Thanks for any help,
Steve in Ann Arbor (again)


         ____
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        |    \_-==-,
   _____|           \
   \                 }
    {  ,.      *     %   Steve Robertson
     `/  \        ,/'   Research Fellow
          ~\    ,/   UofM Radiation Laboratory
            @, /   http://www-personal.engin.umich.edu/~svr/
             \!