How often to change Compact Fluorescent Lights

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!

wrote in message
ups.com...
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!

I've read but can't verify as yet (my lights are only 2 weeks old) that
T8/T12's can diminish their output by as much as 50% in the first 6 months,
and the T8's and T5's can go 30% longer, so 8 months sounds about right.

I plan on changing mine every 6 or 7 months, as I am quite paranoid about
lumen, spectrum and CRI output for my new tank

Oz
--
My Aquatic web Blog is at http://members.optusnet.com.au/ivan.smith

Ozdude Wrote:
wrote in message
ups.com...-
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!-

I've read but can't verify as yet (my lights are only 2 weeks old)
that
T8/T12's can diminish their output by as much as 50% in the first 6
months,
and the T8's and T5's can go 30% longer, so 8 months sounds about
right.

I plan on changing mine every 6 or 7 months, as I am quite paranoid
about
lumen, spectrum and CRI output for my new tank

Oz
--
My Aquatic web Blog is at http://tinyurl.com/6d5ju

most ppl use them till they burn out the plants can anjust to the
spectum shift due to "diminishing" i know alot of ppl running very
great looking planted tanks on 1-2 years old tubes, theres a bloke in
USA that happy takes ppls "old" tubes if they change every 6-12months
if u got the money change every 6 or so months but most ppl use till
they dead.


Gavin


--
nitromad

In article . com,
wrote:

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.

CF's are supposed to be good for plant growth for up to a year but this
can be shortened by the amount of heat in their enclosure. I've found
that mine (in a relatively hot hood) were good for less than a year. The
best indicator is when you observe changes in the tank i.e. algae
growth, slower plant growth.

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

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

Dude, tinyurl.com

I use them till they die.

Looks like the sensible thing to do. Unless there is more to aquarium
lights than lumens. Is there?

--
Victor M. Martinez
Owned and operated by the Fantastic Seven (TM)
Send your spam he
Email me he

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

kev wrote:
http://www.gelighting.com/na/busines..._resources/lit
era ture_library/sell_sheets/downloads/fluorescent/28345_starcoat_t5
_linear.pdf

Dude, tinyurl.com

Heheh I know, I know.


I use them till they die.

Looks like the sensible thing to do. Unless there is more to aquarium
lights than lumens. Is there?


I'd imagine that the photosynthetic parts of the spectrum output curve
matches the lumen curve unless the phospors degrade in a manner that
doesn't affect what our eyes see.


kev

--
Civilization.

An organized system of alternatives to the stone age - CJCherryh

In article . com,
wrote:
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...

Well, there's one way to find out for su get one new one and compare it
to the old ones. The anal retentive and wealthy re-tube at 6 mos. I just
use twice the number of tubes and replace them when they burn out.
--
Need Mercedes parts ? - http://parts.mbz.org
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633CSi 250SE/C 300SD | Killies, killi.net, Crypts, aquaria.net
1970 280SE, 72 280SE | Old wris****ches http://watches.list.mbz.org

In article ,
Victor Martinez wrote:
kev wrote:
http://www.gelighting.com/na/busines...sources/litera
ture_library/sell_sheets/downloads/fluorescent/28345_starcoat_t5
_linear.pdf

Dude, tinyurl.com

I use them till they die.

Looks like the sensible thing to do. Unless there is more to aquarium
lights than lumens. Is there?

Nope.

Prove it to yourself. Try a pair of really old high CRI full spectrum 10K tubes
then try a pair of new cool/warm whites and observe the difference.

In other words, yes Virginia, new $7 tubes work better than old $40 tubes.

--
Need Mercedes parts ? - http://parts.mbz.org
http://www.mbz.org | Mercedes Mailing lists: http://lists.mbz.org
633CSi 250SE/C 300SD | Killies, killi.net, Crypts, aquaria.net
1970 280SE, 72 280SE | Old wris****ches http://watches.list.mbz.org

In article , Richard wrote:
Well, there's one way to find out for su get one new one and compare it
to the old ones. The anal retentive and wealthy re-tube at 6 mos. I just
use twice the number of tubes and replace them when they burn out.

It would seem to me that's not a very cheap solution, the extra
electricity costs will outweigh the replacement costs of the bulb...

The 6-month guideline is generally only for super-light hungry reef
tanks (which I also keep) - and even that is up for argument. In
my planted tanks I replace my bulbs about every year or so, by then
there's a significant -and noticeable even to the naked eye- drop
in light output. My plants sure do grow like crazy after a bulb
change.

-Eric