On 12 Jan 2005, the world was enlightened by 's opinion about...

Hello,

How often do most of you change your CF bulbs? I've got some of the
long 55W & 65W bulbs that I've been using for about 8 months. I'm
starting to suspect a measureable decrease in light output from the
changes I'm seeing in my tank. Maybe I'm just paranoid...

Thanks!


In general, T5/PCF bulbs should hold 90% of their rated output for the
life of the bulb (~20,000 hours or about 4.5 years).

Here's a link to GE's data sheet for T5HO bulbs (PCF are folded T5s),
scroll all the way to the bottom of the .pdf to see the lumen maintenance
graph:

http://www.gelighting.com/na/busines...sources/litera
ture_library/sell_sheets/downloads/fluorescent/28345_starcoat_t5
_linear.pdf

I use them till they die.


kev

--
Civilization.

An organized system of alternatives to the stone age - CJCherryh