small space big light!

It will be magic I have a 400w hps/mh grow in a 4ft wide by 6ft tall and 2.5 deep. And my temps sit at about 75 average. I use a 400cfm exhaust fan with a speed controller so I can dial in the temps.

 

It will not be magic. It will be a pain in your ass to deal with.

Honestly, for a 2x2, just get a 250w and save yourself the headache. Attic grows are a pain in the ass on their own because of temperature fluctuations. A 250w will more than sufficiently light that area.

A 400w in that area is probably going to require a 6" inline fan dedicated to the cool tube, and a 4" fan and carbon filter for venting the cab. And even then the radiant heat is going to be ridiculous.

 

I use one 6 inch for filter and cool tube with no booster fans and works amazing.

 

In a space more than twice as large as his.

 

so your telling me a 600 hps would be hard to manage in a 2.7x2.7x5 tent? becuz I'm bought to buy one for my tent D:

 

Eh, not will be. Could be. A lot of people run 600's in 3x3's. I personally prefer 400's for 3x3's. Too many variables - I had trouble cooling a 400w in a 2x3 a while back. With a 6" vortex AND a 4" vortex.

I look at it in terms of efficiency. a 600w will not give you 200w worth of bud more than a 400w, this isn't because the 600 is not capable of it, but because the 600w is capable of lighting a bigger area.

I did a test a while back with 600's and 1000's in a 4x4 tent. One would assume that the 1000w would yield quite a bit more when grown from clones of the same mother plant. Yes, the 1000w did yield more (a bit over an oz) but that's 400w of energy we're talking about. I could put a 400w in another tent, pay the same amount in electricity, and get a half lb as opposed to an oz.

I've never run a 1000w in a 4x4 since. Never ran a 600w in a 3x3 since then either, for the same reason.

But yes, a 600w will give you denser nugs than a 400w in there.