Changing our PL lights

**|squee|** · 18th Sep 2005, 11:42

Read this.

From the above, (I assume compact flourescents are called PLs here) is it advisble to change only when they run out? Or is that untrue and we should change them every six months or a year?

**PeterGwee** · 18th Sep 2005, 12:17

I use them until they burn out....

Regards
Peter Gwee

**Bug}{** · 18th Sep 2005, 14:17

Noticed that the tubes which are going to burned out giving much lesser light in terms of brightness.Anymore people can comment on their light tubes changing regime?Thks

**Justikanz** · 18th Sep 2005, 14:19

Noticed that after 6 months, the intensity drops quite a lot! Just bought another 110W to up the WpG... Only then did I realise that the old PL tubes' intensity had dropped quite a bit... Now I am so tempted to change the old PL tubes...

**Bug}{** · 18th Sep 2005, 14:37

Looks like its time to change tubes.Nice looking time you have.Just checked out your blog

**xxdivinityxx** · 18th Sep 2005, 22:57

Terence,

I felt i needed to clear this up.
Over in the US (and Australia too) they call PL Lights CF (Compact Floros), which actually is a case of mistaken identity.

CF refers to the type we find in our homes, with screw in ends and usually rounded or shorter 'U' portions.

PL however is what we usually use in aquarium lighting. Contrary to popular beliefs, Although FL stands for Floroscent Lighting, PL is not an acronym for Power/Philips/Plant lighting.

PL lighting simply represents the model which they are classified under. If you walk into a lighting specific hardware shop and ask for a Linear 4 pin PLL, they'll get you what you're after: Our standard 36-55w PL lights.

Don't ask me how they came up with the model number PLL (im assuming the last L means 'Light'), but i'm pretty certain about this mix up. So technically, if our dear friends overseas refer to a CF setup, i can only assume he means the screw in type.

With all that said, Pota(e)to, Pota(h)to, Toma(e)to, Toma(h)to, they all still belong to the same genus:
Lighting sp. 'Aquarium' .

However on the topic of replacements, unless you're measuring in Lumens per Square Inch (LSI) then it matters, so if you're measuring in WPG, it won't make any difference.

Treat your plants right with good fertilising and quite honestly those few lumens lost won't make any difference.

Btw, the usual guage for change is:

FL - 6mths
PL - 8mths - 1yr
MH - 1/1.5yrs

**|squee|** · 18th Sep 2005, 23:16

Looks like both Western and Asian countries got this wrong

Thanks for the clear-up Jerome. It's Terence btw, no double r.

I've been changing mine every six months. bummer.

**xxdivinityxx** · 19th Sep 2005, 02:08

Originally Posted by |squee|

I've been changing mine every six months. bummer.

There's no right or wrong about this, if you're feeling rich, change every 6mths. Of course the difference is noticable. I'm striking the balance between using the age of the tubes as an excuse for poor growth, the slight difference vs unnecessary spending.

But what i'm getting at is that unless you've covered all areas (C02, ferts) and still aren't getting the results you want (highly unlikely tho) then perhaps a change in lighting is warranted.

However this applies for larger tanks (4ft and up, IMO). I've grown the HC in my 2ft Iwagumi with 3 year old tubes without any worry.

**PeterGwee** · 19th Sep 2005, 10:28

Good high CO2 will help improve light usage efficiency down to the light compensation point. Unless you are running at the lower range say 1.5w/g or less and use NO FL, you are unlikely to run low on light as long as the light is evenly spread out. (don't let the plants at the bottom get overshaded.)

Regards
Peter Gwee

**neon** · 19th Sep 2005, 10:59

Sorry bro off topic for this.

The same reason for the frequency and the cost of changing the PL tubes especially for big tank , prompted me to straight getting MH.

But there always a feeling that other people tank light are better syndrome, especially comparing PL vs MH lighted tanks. I find that in PL lighted tank fishes and plants' shapes and color get more 3D effect than the MH. Especially cardinal top blue is much "neon light" under PL , wherelse under MH is just quite plain as the light is too bright.

Just my 2 cents view !

**lorba** · 19th Sep 2005, 17:47

You can try using pink arcadia tubes together with the MH light. Using the Iwasaki MH bulb with 96CRI and 6500K. Red plants will look better this way.

Osram MH is 6000k and greenish.

**neon** · 20th Sep 2005, 22:19

Originally Posted by lorba

You can try using pink arcadia tubes together with the MH light. Using the Iwasaki MH bulb with 96CRI and 6500K. Red plants will look better this way.

Osram MH is 6000k and greenish.

That is a good idea ! The MH light that I am using is Astra Lux 8000K 15OW , which is white and brighter than the osram MH (I find Osram more toward orangy and yellowish).