No, they degrade over time.........Its no different with ther UV
lights in a UV used in the pond or the UV's used in hot tubs and spas
to kill bacteria........over time the bulb does degenerate. We have a
UV on our hout tub, and you can tell when its getting to the point of
needing to be replaced. Id you look at most any manufactuers info,
they spell it out that most bulbs will have a lifespan of usefullness
for about 3 years time, before needing replacement..........we have
seen this first hand wtyh the hot tub. The substance in the bulb over
time of being charged electrically and with the heat inside the bulb
causes it to degrade............So even if the bulb lights up it does
not mean its still good if its around 3 years of age........(actually
that figure is if the bulb is kept on for 3 years continous useage) so
mileage in a pond or aquarium may vary........as a hot tub is usually
left on 24/7/365

On Wed, 8 Jun 2005 09:17:22 +0100, "Oxymel of Squill"
wrote:

===do they seriously degrade, or do they keep working so long as they light up?
===
===cheers
===
===
==="~Roy~" wrote in message
et...
=== The bulbs
===


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Put some color in your cheeks...garden naked!

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