light question?

hani

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am about to set an office tank, 75 g, 41w x 24.5H X 17.5 D, the tank comes with 2 T5 HO 39W EACH tube total 78w , so i bought another light fixture same set up make the total 156 w, am thinking to get a third one to make it 234w wich will give 3watt / gallon.
the tank is 24.5 inch H and the T5 are 36inch w 5 inch shorter than the tank.
should i get the third light fixture, or should i stay at 2w/g mark
co2 will be used
thanks
 

Gerryd

Plant Guru Team
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Sep 23, 2007
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Hi Hani,

I would only use MAYBE the second fixture.....

Remember that more light requires more c02/ferts..

It may be harder to keep c02 demand steady for 3 wpg....

Try it with just the original fixture first and see how it works for a bit..

You can ALWAYS ADD more light, is harder to remove it........
 

hani

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Jul 27, 2007
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thanks Gerryd,
The reason am thinking to add another light bc of the tank H, which is 24.5 in.
At home am running 29g tank with 2x55 wt, i have both lights on at the same time for 2 h at noon , and the rest of the day with only one .
i was thinking doing the same except at home am using AH light system, not T5.
The original fixture will give 1 w/g which seems too low.
hmmm, dont know..
thanks
 

JDowns

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I agree with Gerry. The second light fixture at 156w should be more than enough light. I have a 24" tall tank and run 240w, 3 x 80w bulbs 16" off the waters surface and have no problems growing any stem out there.
 

Tom Barr

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Jan 23, 2005
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I have 1.8 W of T5's on a 120 Gal and it's 24" deep + 8 inches above the tank, plenty of light to grow any species you want...........

Regards,
Tom Barr