25w per square foot doable?

Hey guys,

I am currently starting my first grow, I have a 400w light and I am doing the grow in a 4x4 tent. I know this is a slightly larger than ideal footprint for using a 400w, and it is generally suggested to do 4x2, 3x3 or even some suggest 2.5x2.5 to make the most of this light.

I know I could easily get away with a 600w in this space, and would obviously get better results in doing so. But for various reasons that isn't an option for me right now, I was put in a position where a 4x4 tent of better quality was cheaper than a lesser brand 3x3 tent, so I went for it with the justification that it will be easier to upgrade down the line.

What I would like to know is will I actually somehow grow less weed using a 400w in a 4x4 tent than I would in a 3x3 tent?

It doesn't make much sense to me that there would be any real difference, as long as I try and arrange my plants as close to a 3x3 foot print as possible it seems like the extra space around the plants would be beneficial for me to move around and also in making humidity less of an issue in flower.

The only real potential drawbacks I can see from the added footprint are that I will lose some lumens reflecting back off the walls of the grow tent, but I can't imagine in the scheme of things this would make a huge difference. The only other potential drawback I can see is that I will lose some of the heat of the lamp and since it is currently winter where I live the grow space may run a few degrees cooler than is optimal. Equally though, this would be an advantage in summer when the weather is hotter.

Basically I am wondering if I am going to produce dramatically less from this light than I would if I were to run the same setup in a slightly smaller tent? If I would produce dramatically less then some assistance in understanding the reasons for this would also be appreciated!
 
Yeah it's pretty low I have 4x4 tents and I run 600s, I would just go with 3x3. Same yield probably, and you're not wasting space. Spend the $10-20 you save on some 120mm or 140mm computer fans, crack a window or run some ducting and you'll have good humidity and thicker stems. If you're not ventilating there's gona be condensation all over the tent and your room will stink no matter what size.

Forget your winter temps, HPS are pretty much heaters anyway! I run some tents in the day, my DWC buckets went down to 6C last night no problems, I nearly froze though lol.

Larger tents are also harder to set up alone without damaging and a PITA when you have to shut down your grow in a hurry and move it. I used to have a 6x6 tent but now I never go more than 4x4, I have 5 of them now :D
 
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BustinScales510

Well-Known Member
You can totally grow with a 400 in a 4x4, I mean you could use a 400 in the middle of an empty room. Just imagine the bulb is in the middle of a 3 foot square and any of the plant matter that is outside of that area wont really produce much weight, so try and keep a canopy that is within that and not have a bunch of shaded out poorly lit branches on the outside.
 

doubletake

Well-Known Member
Use the bigger tent since you saved there, just space them Nicley not too far but not too crowded.
I think this might even be nicer then when I had my 1000 in a 4x4 they got huge and over grew the tent and it was hot kinda a hassle

You'll be good
 

jondamon

Well-Known Member
I use a 400w in a room that's 7ftx3.2ftx8ft.

My active growing area is 3x3.

I'm actually glad of the extra space as it helps me to deal with temps better, I have fans mounted on walls, dehumidifier in a corner etc etc.

My yields are above average around 400g dry from 4-6 week veg period and about 65 days of flowering.




J
 

ayr0n

Well-Known Member
I use a 400w in a room that's 7ftx3.2ftx8ft.

My active growing area is 3x3.

I'm actually glad of the extra space as it helps me to deal with temps better, I have fans mounted on walls, dehumidifier in a corner etc etc.

My yields are above average around 400g dry from 4-6 week veg period and about 65 days of flowering.




J
400g from a 400w sounds damn good to me. If I pull out 600 grams from my 600w in this 32" x 32" tent I'll literally shit myself - right on the spot.

I have a feeling I'm wasting a lot of electricity for no reason now...
 

jondamon

Well-Known Member
400g from a 400w sounds damn good to me. If I pull out 600 grams from my 600w in this 32" x 32" tent I'll literally shit myself - right on the spot.

I have a feeling I'm wasting a lot of electricity for no reason now...

I've honed my skills and keep pretty healthy plants from start to finish.


Some folks on RIU call bullshit every time I say 400g but each of the below weights have been documented on RIU with weight pics.

My last few harvests have been.

401.5
379
427
439g

So I say around 400g.

My aim is to exceed 450g.

I watch leaf health closely and grow in coco feeding every watering.



J
 

ayr0n

Well-Known Member
I've honed my skills and keep pretty healthy plants from start to finish.


Some folks on RIU call bullshit every time I say 400g but each of the below weights have been documented on RIU with weight pics.

My last few harvests have been.

401.5
379
427
439g

So I say around 400g.

My aim is to exceed 450g.

I watch leaf health closely and grow in coco feeding every watering.



J
Nahh I believe you man. 1g/w is definitely possible. That's awesome.

Pretty sure 1.25-1.5g/w is feasible in near perfect conditions w/ SOG running 12/12 all the way through...almost positive I saw a journal where someone pulled that off. I'd be more than happy to pull 0.5-0.75/w but I'm just starting out so prob not.
 
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Sativied

Well-Known Member
... from my 600w in this 32" x 32" tent...

I have a feeling I'm wasting a lot of electricity for no reason now...
Yeah 600 watt is overkill for 32x32", quite a bit too. 400w would be plenty already (which fits 3x3' or 1m2 nicely). I use 600 watt on 48x48" / 4x4'.
 

Sativied

Well-Known Member
Do you think 2000 in a 8x8 is good?
A 600w per every 4x4 would work nicely.

4x4 4x4

4x4 4x4

You could leave out 1x8' in the middle for access to the plants.

1000watt is suitable for 5x5 roughly. Fitting 2x 1K watters in 8x8 is hard simply because of the square space. If it would have been something like 6x11 (almost same size) then 2x1000watt would have fittted quite well but on 8x8 4 bulbs would give the best coverage (see rolling dice :) ).
 

skunkd0c

Well-Known Member
What I would like to know is will I actually somehow grow less weed using a 400w in a 4x4 tent than I would in a 3x3 tent?
you should get at least the same or possibly more if you can fill every bit of space with a main cola (sog) you will yield more
but the quality will not be as good the nugs will not be as dense as under a 600 or a 1000

peace
 

doubletake

Well-Known Member
Ya I get ya on coverage 4 lights would be better I'm just kinda screwed I had a 4k room moved and sold two lights so I only have 2 1000 watt ballast

So could I do like more of a rectangle and leave a open foot on both sides eft and right to walk down?


---XXX---
---XXX---
---XXX---
---XXX---

Kinda like this ^^ Xs are plants and the side things are walkways
 

skunkd0c

Well-Known Member
most lights/reflectors will put out better coverage at the sides of the reflector rather than at each end of the light
so a 600w is more like 4x3 or maybe 6x3 you could get away with in some reflectors like the adjustable wing reflectors
if you keep the plants short a 600 can still grow good bud/ sog plants 2ft away from the colas which will give a bigger footprint
 

Sativied

Well-Known Member
In that case yes you have few options and access from both sides is certainly convenient. You could cover close to 6x8 that way.

If the hoods aren't square, hang them like so:

|
|

Instead of:

_
_
 

doubletake

Well-Known Member
In that case yes you have few options and access from both sides is certainly convenient. You could cover close to 6x8 that way.

If the hoods aren't square, hang them like so:

|
|

Instead of:

_
_
Got ya man yeah they are the square hydro farm I think there called
I want the magnums xxl to really cover the space
 
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