Question about Negative Pressure

[chib]

Hello everyone,

I run a 3x3 with a 6 inch 288cfm duct fan, but even with the fan on minimum and 2 open vents the walls are still pulled in quite a bit.

I currently do not run a carbon filter at the moment but things might change in the future.

Would I be better off just getting another duct fan but 4 inches in size? Or maybe secure some bamboo poles around my tent to avoid it from being sucked in? I'd rather not buy another fan if I don't have to... Also opening a lot of vents is annoying when the tent is located in my bedroom and I have to constantly turn lights on/off during the dark periods.

Thanks

 

[TysonOG]

I use a 4" duct fan in my 3x3, it works more than enough. Still has negative pressure but it doesn't suck in the tent walls that dramatically. You can also open one of the ceiling holes, the light leak is not that bad.

 

[Skunksta]

I agree with the above.
But if money is not an issue.
You can get controllers that will manage that.
Or you can buy fans with one on. (sounds like you have one)
I use one as i find my zips last longer on tents.
6 inch in and 5 out with a filter on the 6inch.
RVK fans both at 100% even with the filter i get suck in but also have longer run of ducting on the 5 inch.
My sweet spot is %33 less on my 6inch than the 5 inch and no negative pressure.
Hope that helps some.
AC infinity and marshydro do some nice controlled fans

 

[Buds Buddy]

I don't use inline fans in a 3x3. I use a 6" Clip on Fan mounted inside one of the duct ports for exhaust at the top of the tent. On the bottom (opposite side of tent) I use a 6" clip on fan inside a duct port for intake air. I also use a 3rd one just to move air around in the tent. Works perfect. Fans were $8 each at Walmart.

 

[Roy Growin]

The negative pressure is a good thing, shows good airflow
Ideally you want that fresh air pulled in at the bottom and warm used air pulled out at the top
A small 4" inline is ideal in summer, but otherwise I just use a short section of ducting to hold the vent fully open and a) put a u-bend in it to prevent light leak and b) a stocking over the outside end to prevent bugs getting sucked in
Get fresh air into the room daily and you're good to go
Whether you need a odour filter or not, it is a good idea to filter your air to remove dust and pollutants
A circulating fan is also a must, as BB asserts

 

[bobrown14]

Turn the fan down?? They sell add-on fan controllers. I use them. But I still run my fans on full.

You're gonna need a filter at some point unless its cool for your home to smell like weed cause its going to smell like weed inna bit.

We live way out in the country and I still filter and also use merv-13 filters in our air handling system which removes covid so cannabis smell also removed.