Amount of light required for 4x2x1.5 ft planted tank

[cheeboonyong]

Hi, thinking of starting a 4x2x1.5ft (2 is height) tank and planning for the lights. Basically starting a planted tank. After reading the forums, I have the impression that to grow riccia would require 3Watts or more per gallon. So going by that, my calculation is as follows:

4x2x1.5=
91.84 US Gallons or
84.95 Imperial Gallons or
339.8 litres

at 3 Watts, works out to:
275.5 Watts

I'm thinking of getting 2 sets of 4x36 watts lights from Chan (NA), which works out to 288 watts.

Just seeking opinion from people here if there's anything wrong with my calculation.

Also, if I choose NOT to grow riccia but just "usual" plants which are not so light demanding, how much watt per gallon would I need?

Many thanks
Boon Yong

[tawauboy]

you calculation looks good.
and you are using us gallons, which is correct.

if you get 288 watts of lighting, you'll have more flexibility and choices in the plants that you can grow. if possible, maybe you can get nature to put 2 switches for each set of lights. this way will allow you to switch your lighting in multiples of 72 watts.

[benetay]

Remember to cool your tank too, as light do emits alot of heat and therefore heating up the water colume which some plants need a cooler water to trive upon.

[cheeboonyong]

thanks guys for the advice. I just tried an experiment with a fan just 3 days ago. Bought a 16W AC fan from Sim Lim Tower. Brought my tanks temp from 29-30 to 26-27 degrees (current tank is 2.5 ft long Juwel tank). I think for 4 ft tank, 2x same fan should do the trick.

[benetay]

Yes having 2 AC fans will do the trick as long as u don't mind the noise level and the amount of evaporation thou.

[cheeboonyong]

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On 11/25/2002 11:33:18 PM

Yes having 2 AC fans will do the trick as long as u don't mind the noise level and the amount of evaporation thou.
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I suppose the noise level depends on the fans. I bought the Toyo brand fan, made in Japan. Very quiet. does not have the very high pitch sound that you get in some fans. of course, still have some basic level noise level, but acceptable to me. $20 each fan. got cheaper ones from taiwan, $5-$15. But i suspect will be more noisy...

[benetay]

Have u tried using those AC fan that is ready made just plug and play kind? Cost $30 each i got 3 of them i'm not sure about upgrading them to a bigger vol so i can blow more surface area to maximise the evaporation rate then tusk lowing the temp.

[cheeboonyong]

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On 11/25/2002 11:51:10 PM

Have u tried using those AC fan that is ready made just plug and play kind? Cost $30 each i got 3 of them i'm not sure about upgrading them to a bigger vol so i can blow more surface area to maximise the evaporation rate then tusk lowing the temp.
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not sure what u mean by plug and play. the toyo fan i got came with a cable. so literally, yes, plug into the power socket and it works, if that's what u mean. cable costs $2.50 each.

did u do your own fan mounting? I got a picture frame from sagacity in bras brasah complex, which fits the fan to a glove. i have a central light, so basically now balacing the fan on top of the frame, which in turn lies between the edge of my central light and the edge of my tank...

[benetay]

Those ready made AC fans have clips which u can just clip them onto the side of the tank and ready to blow [:]

[tawauboy]

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did u do your own fan mounting? I got a picture frame from sagacity in bras brasah complex, which fits the fan to a glove. i have a central light, so basically now balacing the fan on top of the frame, which in turn lies between the edge of my central light and the edge of my tank...
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make sure that it is secure enough so that it will not drop into the tank. if it does, it will trip you elcb and make sure that the mains are off before any attempts to retrieve tha fan.

[benetay]

My fan drop once into the water, it didn't trip my elcb. I remove the wire instantly and took the fan out. clean it dry and try to run it again but it failed. So took out my meter and test for Ohmz and there is still reading so i guess it's still fine.

Took the hair dryer and blow it dry...fix it back, yuP! it' works.

[vinz]

You can get fan clips from Nature Aquarium. Not sure if he has stock. It's by ISTA and I've not noticed it elsewhere. They will fit 12cm and 9 cm fans. If you cannot find them, call Aquanautics (distributor for ISTA, pls check phonebook for contacts) and ask them which LFS orders from them.

[FC]

Hi Cheeboonyong,

Just a word of caution, if you use direct AC fan, make sure you earth it. Usually, there is 2 threaded screw holes there, connect the earth there with a wahser and a screw.

I am aslo having a 4 footer and 1 fan is enough. I use the clip from NA and mount it such that it blow on the water and also flow under the light. 2 things are achieved:
-water cooling by evaporation
-lamp heat is warded away

The disadvantages of the PL light is that there is a dark break in the mid of the lamp. That is, the middle of your tank will not be sufficiently lighted, you may have to consider it in your plant layout.