Grow tent ventilation advice needed.

Hey everyone! I'm no stranger to Rollitup but this will be my first post.

I am setting up a 40" x 40" x 78" tent with 600w cooltube MH/HPS.

I am most concerned about the sound/smell of this grow and would like to keep it to a minimum.

I am stuck on what type of fan/filter to go with. I would like to go with the following : filter-ducting-light-ducting-fan (pulling from outside) then roughly 6 feet of ducting to the window.

Will a 4" inline fan with 4" carbon filter be sufficient for this? With a 4" fan I would need 4" to 6" couplings to and from the light as it is 6".

I like the 4" combo because of space limitations and I would think the 4" is a bit quieter than a 6" inline but is it going to move enough air?


Thanks!

Happy growing

That should be plenty for that size tent. You should be fine with the 4"

i have always used a 6" fan for that size tent and never had a problem, i could see that in summer heat could be an issue depending on a lot of factors of course.

obviously a 6" fan is a lot louder than a 4" so if noise is more of a concern than maintaining a stable environment then plump for the 4". if you want to buy once get the 6", i guarantee that will work.

If sound is a concern, a 6" fan dialed down may be more quiet than a 4" fan on full.

When I bought my exhaust I went all out and am currently dialing it down. I figured if I needed to upgrade in the future I would already have a nice big exhaust fan.

/\ wise thinking/\

just make sure you get a decent quality speed controller or it can make the fan louder lol

Get a variac transformer instead of a speed controller with a 6" if your summers are hot. My 6" 400cfm centrifugal on 70% can barely be heard directly behind the wall from my tent.

go 6inch if you can, esp if you are going to run a 600

Late reply but thank you thank you! Took your guys' advise and the 6" is perfect!