Negative pressure

[Nute]

Hey guys just wanted to ask for those of you using tents how good is it to have negative pressure in your tent mine is consistently sucked right in I think it's a good thing. Any opinions Also what is the positive or negative of having this in your tent

[Nute]

Here is what I found
Why Negative Pressure Take Place in A Grow Tent?


Negative pressure indicates to have less air pressure inside an enclosed area comparing to the outside. A physics 101 is, when the air density inside an area is less than it’s surroundings, a negative air pressure takes place. As a result, the boundary of the enclosed area tends to pull inwards(concave).

So how does this apply in the growing regime? Well, when the rate of air leaving the grow tent(through exhaust fans) is more than the rate at which air enters(through intake fans) is higher, then you can say a negative pressure taking place in the grow tent.

And these are the two situations where a negative pressure can take place-

• When the outtake fan is too much efficient than your intake fans.
• When the intake fan is drawing way less air in than what it’s supposed to do theoretically. This might take place when there are some large kinks(compression) in the intake ducting.

If you want to learn how to get negative pressure in grow tent, playing with these two variables will get you the desired result.
How Does Grow Tent Negative Pressure Affect on The Yield?


Slight negative pressure is good for maximizing the yield of a grow regime. It makes it easier to control the temperature, humidity, CO2 levels and other contaminants of the tent. That’s because when the hot and humid air exits the tent quickly, these consequences follow to drop down.
Also
Apart from these environmental benefits, there are some other benefits of slightly negative pressure in the grow tent-

Avoids the risk of mold or mildew formation on plants.
Lets you do only a few small atmospheric adjustments for different growth stages of the plants.
Keeps the unwanted odor under control and keeps from lingering in the tent.
Having said that, is negative pressure good in a grow room?

Well, too much of everything is always bad. And the same does for negative pressure as well. So, how would you understand if the negative pressure had exceeded the limit or not?

The simple trick is- if the tent itself seems to pull itself inwards, the negative pressure is still under the tolerable limit. If the pressure gets as high as it bends the poles inwards, that’s where the danger limit starts.

So, if you see the poles to bend inwards, the negative pressure is something to worry about. Otherwise, if it’s the tent itself if pulled inwards slightly, you don’t have to worry about it.

[9fingerleafs]

Just make sure it's filter then fan then lights. If You put filter then lights then fan (pulling) it Will draw unfiltered air from the hoods and the smell Will get out. If You push filtered air thru the hoods any leak will go back into the tent. Negstive pressure is the only way to control smell. Im not a tent grower

[homegrown]

Yes negative pressure is good for a tent grow. Its a good indication that you have decent air flow and exchange. I run my filter outside my tent and have no odor issues. When i seal it up for the night the sides can indent a good 4 inches.