Re: Lamp life

I haven't measured light drop-off with any instruments, but I am currently 
under the impression that the intensity drop-off associated with multi-phosphor 
lamps is due to the following conditions:

1. Multi Phosphors:  Some of these phosphors may just not last as long as the
                     one used in cool white lights.

2. Heat: This can play a factor by itself in reducing the effectiveness of
         the individual phosphors, as well as in causing them to react with
         one another, perhaps reducing their effectiveness.

3. Build Quality: I have had my single Triton on my tank for two months now
                  and find it to be finicky at best.  Sometimes it just 
                  doesn't want to start.  My Ultra Tri-Lux kicks off instantly
                  every time.  The Triton and the other bulb on its fixture
                  are dark on the ends after this short time.  The Penn-Plax
                  and the other bulb on that fixture still look nearly new.
                  This could also be caused by a bad ballast, I suppose.

I intend to see if I can eliminate the ballast difference in the near future by 
switching to a high-quality electronic ballast.  I suspect that this will help, 
but we'll see.  I also intend to begin using T-8 bulbs when available in the 
color that I want.

BTW, on my 20h tank, I just went with 2 agro bulbs, 1 cool white, and 1 
daylight.  They provide an attractive color pattern.

David W. Webb
Enterprise Computing Provisioning
Texas Instruments Inc. Dallas, TX USA
(214) 575-3443 (voice)  MSGID:       DAWB
(214) 575-4853 (fax)    Internet:    dwebb at ti_com
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