Fluoresent Light for 120 cm tank.

[aukc]

Hi,

I got a curved front glass 120cm tank with a aluminium/plastic hood installed with 3 x 30w lamp.

From my own calculation, water volume is about 70 US gallon.
At 2 watts/gallon --> 140 watts or 4 x 40w
at 3 watts/gallon --> 200 watts or 5 x 40w


The 36w FL tube cannot go into the hood because the tube is longer than 120cm. Do I need to DIY a hood or is there any commericial hood?

In case I need to DIY a hood, has anyone use those round FL tubes in planted tank before? I saw some Panasonic triphor 6700K extra bright tubes, called PA Look. I wonder if they are good for plants.

One more thing, there would be a lot of heat generated by the 160w to 200w of power over the water. How do get ride of the heat so as not to raise the water temp.

Thanks for any suggestion.

[juggler]

Can consider using PL lights. They are shorter but have more wattage.
Eg. a 36W PL light is about 17" only. Can put 2 pieces end to end in your hood. For 6 pieces, you can have 6x36W = 216W in your tank.

See this recent discussion thread http://www.aquaticquotient.com/phpbb...ic.php?t=14725

If you like, you can also approach Nature Aquarium (see LFS list above) to get them to help you modify the hood.

[tawauboy]

you can look into pl tubes, which are more compact than fl tubes. common wattage are 18w, 36w and 55w. if you are not into diy, you can bring you hood to nature aquarium to have it modified.

normally, fans are used to cool the tank or you can raise the lights higher. either way will reduce tank water temperature increase. if cooling to 25 deg c is required, you’’ have to look into a chiller.

[bttay]

I DIY 4 x 55w PL for my 4ft

[aukc]

Thanks for the suggestions.

PL lamps are more expensive as compared to straight tubes. And also where to get 36w or 55w PL and what is their est. price. I know that philip TLD 36W/865 is only about $3.50 but have not seen the high power (36W/55W) PLs.

Just to understand wattage requirement calculation better. When we say we need 3W/Gal, does that mean we are referring to the standard lumen output. With modern high efficiency tube like TLD36W/865 that gives out more lumens, we should be able to achieve same light with less watts. Any comments about this?


Regards

[aukc]

about the the DIY hood again.

The dimension is about 120 x 45 cm. 45 cm is about 18 inches.

Do I need to spread out the lights so that there is even coverage?

Thanks for the DIY links provided. Juggler's one uses a 4 x 6in PVC.
I think it cannot completely cover the whole tank? Is that OK.
For my case, if I want to use say 4 tubes of 36w straight tube and 4x6in PVC trunking there would be a about 6 inches gap in between. Is this acceptable?

Rgs.
KC

[tawauboy]

pl being newer, more compact and less widely used will definitely be more expensive. big lighting shops and nature aquarium have pl tube for sales.

xx w/gal is to be used as a guide. normally lumen output is not taken into account. no two tanks are the same so you may be able to use less tubes. do remember that fl tube light output will reduce over time.

ideally, you'll want your lights to provide even coverage. spread you total light power evenly and use a reflector. if you want to grow high light foreground plants, you can place your light tubes closer for the fron of tank. it all depends on what you want.

[bttay]

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On 12/18/2003 12:44:10 AM

PL lamps are more expensive as compared to straight tubes. And also where to get 36w or 55w PL and what is their est. price. I know that philip TLD 36W/865 is only about $3.50 but have not seen the high power (36W/55W) PLs.

----------------

I just bought 4 x 55w tubes and 2 ebalast. Cost me $130 plus.

[aukc]

Hi,

Heard of the expensive PL lamps.
4 x 55w PL = $130.00. Are they the high efficiency type?
I know there are some which is not that bright. I happen to buy 2 different make of PL lamp for the kitchen in my home. Even having the same wattage (11W), the Panasonic PA-LOOK one is so much brighter that the "SAFE" tube. There are 2 PLs( 1 is Panasonic, 1 is SAFE) in one housing, I can see the extra bright Panasonic even after the frosted glass diffuser.

Cost of Philip TLD36/865 (high lumen output) = $3.50 to $4.00
(price varies with shop)
if replaced by 36w Philip. -> 6 x 36W = 6x $4 = $24.00
Cost of normal FL tube = $2.5 ( or less)
6 x 36W = 6x $2.5 = $15.00

The PA-LOOK from Panasonic with a Ra of 88 and Brightness = 3250 lumen.
Cost about $6.00+
6 x $6.00 = $36.00

Hey, no matter how I calculate, the straight FL is still the most economical.
As mentioned, since there are 6 tubes spread out it would be more even illumination of the tank.

[Sleepy_lancs]

True.. about cost.. but you forgot something... Recommended change of lights is every 6 mths for FL lights and PL light well.. usually a year or a year and half. And its rather more environment friendly [:]. Hmm.. and you can use it in your kitchen when its time to change those.... wouldn't that be a good idea. I don't know what to do with mine... lol....

[aukc]

Hi,

Is it true that PL last longer than FL? If anyone know of any information on that, could you post it here.

To my understanding they are essentially the same thing except for the bent glass tube. And I also think they don't need a starter, seems like the starter is built into the lamp itself. I think you pay for the extra process of bending the glass tube and small volume production.

Cheers.
KC Au

[himyick]

The PL tubes are not very expensive, the price of each tube is approx $9~$12 depending on brand. Actually its the e-ballasts that cost more, each one is around ~$25 and can support 2x PL tubes. PL setups are more energy efficient, relatively speaking, as compared to (flouros w/ tar ballast) setup.

However, if you are concerned about the initial setup cost, then you may want to stay with your present 30W flouros setup. For your case, just make sure you get those extra bright tubes (eg. Hitachi EBT, NEC Tri-phosphor, Philips 865s). 30W tubes are rather rare in neighbouhood shops but you can find them in Jln Besar (Kelantan or Verasamy Rd).

Seasons greetings
Himyick