# 2x4 T5 Veg Area - 6 or 8 Bulbs?



## PokeyPuppy420 (Sep 6, 2013)

I'm setting up a 2x4 veg-only area.  I plan to use a 4' T5 fixture.  Should I get a 6-bulb fixture, or an 8-bulb fixture?  I plan to veg 3-4 plants at a time, and maybe some clones/seedlings as well.

8 bulbs would give me 54 watts per square foot.

6 bulbs would give me about 40 watts per square foot.

Thanks.


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## The Hemp Goddess (Sep 6, 2013)

We generally don't use watts to figure how much light we need as different types of light vary so much in the amount of lumens they produce per watt.  For instance, HPS put of between 100 and 150 lumens per watt.  CFLs put out about 60 lumens per watt.  T5s put out about 90 lumens per watt.  If you have 40 watts per sq ft and use CFLs, you will have about 2400 lumens per sq ft.  If you use T5s, you have about 3600 lumens per sq ft, and if you use HPS you would have about 4000-6000 lumens per sq ft.  So you can see how much the amount of light varies between different sources for the same amount of wattage.

With that being said, we generally use lumens to determine lighting needs.  You want a minimum of 3000 lumens per sq ft for vegging and 5000 for flowering.  However, I have found that a 4' 4 tube T5 fixture works very well in my space that is just slightly smaller than 2 x 4.  I think the fact that you can keep the tubes within inches of the canopy makes a big difference.


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## Locked (Sep 6, 2013)

Same here.. Been rocking a 4 foot four bulb HO T5 in my  2x4 veg tent for a couple years now. Works great.


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## oldsman (Sep 6, 2013)

I  run a 4' 8 bulb in a 2x4.Most 8 bulb lights have on/off switches so you can run 4 or all 8 bulbs.


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## Locked (Sep 6, 2013)

oldsman said:
			
		

> I  run a 4' 8 bulb in a 2x4.Most 8 bulb lights have on/off switches so you can run 4 or all 8 bulbs.




True that bro. My 4 bulb has a switch to run all 4 bulbs or just 2.  Good point.


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## Growdude (Sep 6, 2013)

I like a lot of light in all stages, 8 bulb here, 2x4 tent.


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## PokeyPuppy420 (Sep 6, 2013)

One thing to consider (for me) is that I plan to keep my 2x4 veg-only grow tent OPENED at all times, with an external oscillating fan blowing on the plants at all times.  This eliminates the need for an internal exhaust fan and an internal oscillating fan, but somewhat reduces the "reflectivity" aspect...

So I've decided to go with a 4' 8-bulb fixture (T5 Badboy)...maybe a bit of overkill, but a bit of overkill is not necessarily a bad thing...

I love the "single line" of plants (instead of multiple lines of plants) because it makes watering and pruning easy...especially in later stages of growth...


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## The Hemp Goddess (Sep 7, 2013)

I am curious why you have decided to keep the tent open all the time?  I am thinking that the canopy may still get too hot if you are not exhausting hot air out, especially with an 8 tube light.


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