How often to change Compact Fluorescent Lights

[[email protected]]

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!

[Ozdude]

> 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

[nitromad]

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

[Rich M]

In article om>,
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.

[kev]

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/business_lighting/education_resources/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

[Victor Martinez]

kev wrote:
> http://www.gelighting.com/na/business_lighting/education_resources/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 here:
Email me here:

[kev]

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

> kev wrote:
>> http://www.gelighting.com/na/business_lighting/education_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

[Richard]

In article om>,
> 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 sure: 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.
--
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[Richard]

In article >,
Victor Martinez > wrote:
>kev wrote:
>> http://www.gelighting.com/na/business_lighting/education_resources/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

[Eric McGlohon]

In article >, Richard wrote:
> Well, there's one way to find out for sure: 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

[Richard]

In article >,
Eric McGlohon > wrote:
>In article >, Richard wrote:
>> Well, there's one way to find out for sure: 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...

Look at GE's publshed devay curves, it never goes below 50% so I
come out ahead, sorta. We have the cheapest electricity in the
world here.

But, occasionallyll splurge and spend a whopping $7 on a new pair of tubes
so I can't say I really have dim lights.

>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.

Sure, they've never so bright as the first week. Freshwater or
marine there's no such thing as too much light, just not enoiugh plants :-)

--
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