# 36W or 72W for planted tank



## Jaap (Jun 24, 2005)

Hi,

will 36W T5 white light be sufficient for a 90L tank with valisneria and eleocharis parvula or will I need 36W x 2 ? Also I will use pressurized CO2 and EI method.

Thanks.


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## Zapins (Jul 28, 2004)

1x36w should be bright enough to give you medium-high light in the tank if it is a T5 HO light, if not then go with the 2x36w.

90L is about 24 gallons, so I don't think the tank will be deep enough to need any more light if you are getting HO lights.

Any pics of your tank or ideas for a the new layout?


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## Jaap (Jun 24, 2005)

I think the best way to is 72 watts devided by 90L it will give 0.8 watts per littre. As I see from the 2010 AGA Aquascaping Contest most aquariums have lights raning from 0.6-1.2 watts per littre.

My tank is 58cm in height so at 72 watts I dont think the 0.8 watts per littre is very accurate but at least its close to what most aquascapers use.

Agree or disagree?

pics will come up soon thanks


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## Left C (Jun 14, 2005)

Is your lighting T5HO with very good reflectors or is it normal output T5 with only fair reflectors? T5HO lighting with very good reflectors is much brighter.

If it is the higher lighting category, you should follow Zapins advice.

Your 90L is 60cm long, isn't it? I am not familiar with 60cm T5 bulbs that are 36w. Are they 18w, by chance? There are 60cm T5HO's that are 24w and T5VHO's that are 40w.

Something else to consider is if you are going to use CO2. If you have higher lighting, you will definitely need CO2 or maybe an Excel type product will work.


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## Jaap (Jun 24, 2005)

Left C said:


> Is your lighting T5HO with very good reflectors or is it normal output T5 with only fair reflectors? T5HO lighting with very good reflectors is much brighter.
> 
> If it is the higher lighting category, you should follow Zapins advice.
> 
> ...


My tank is tall...it has a height of 58cm and my lights are plain T5 with fairly good reflectors. Each T5 is 36w thats why I consider two of them. I will be dosing EI method and will have pressurized CO2.


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## Left C (Jun 14, 2005)

Maybe you have 36w PC's. Each tube is a T5. Anyway ...

58cm is very tall for an aquarium of 90L. Wow! That is almost 23". I wish that you would of mentioned this earlier. It makes a big difference.

An option is to run one of the bulbs as your main lighting source and the other as a noon burst. It depends on your light selection.


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