Negative Air Pressure

[golfnrl]

I'm getting ready for my next grow. I'd like to address the negative pressure in my grow tent. I don't like the sides of the tent being sucked in...my OCD can't stand the non-uniform lines of the tent , and it infringes on my limited grow space. I am running a gorilla lite 2x2.5x6'11' tent. Currently I have generic 4" fan w/ speed control that runs mostly on high. I have 6" intake ducting. How do I fix the negative pressure effects from this setup? I tried lowering the fan speed but couldn't maintain the temp I wanted inside the tent with the slower fan speed. Or, is negative pressure a good thing and not something I should worry about? I can deal with the OCD

[s62]

Negative pressure is a good thing usually. It helps keep smells in check. I’ve got negative pressure in my Gorilla 3x3, and I used 3’ pre-cut pieces of wood (from Home Depot), plus some zip ties and 3’ dowels to help keep the sides from sucking in too much. Smoke a bowl and put that OCD to rest!

[dphipps1020]

As far as it being an issue for the grow, definitely not something to worry about. However, if you want the sides to stop sucking in, get another exhaust fan and point it so it blows air in. Make sure it's the same strength or less than your 4 inch fan or it will blow the sides out instead. Hope this helps.

[Tersky]

I was researching something else and saw this link just this morning. What are the odds!! No need for an an intake fan with this method. Just PVC and ratchet ropes. Never tried it so dont know how effective it is.
https://www.cocoforcannabis.com/how-...om-sucking-in/

[Toker1]

You have 2 options, negative pressure or positive. Either way your tent shell is not flush with the tent poles.
Negative pressure is recommended. This ensures the smelly weed air gets forced through the filters or fans and not out the tent and all over the room the tent is inside (in an uncontrolled manner).
Negative suction is more efficient at moving air and removing heat than positive pressure is. You get a smooth laminar air flow with negative pressure. Positive pressure created a more turbulent air flow. I wouldn't change that about your set up.
As for the tent walls being collapsed and taking up space. I don’t think that is really an issue. The tent walls are flexible. If a plant pushes on it, the walls move back out and increase the space again. Plus, how much extra space does the bent tent wall really take up? 1/2” on a side? That’s 1” subtracted from the total linear space. Unless the space is 6” (linear) wide, those effects are completely negligible.

[golfnrl]

Thx Toker1...I appreciate the input. I'm going to change fans but not change anything else.

[Toker1]

No prob! Good luck. If you need more info. Don’t hesitate to research and ask more questions. 😃

[golfnrl]

I was researching something else and saw this link just this morning. What are the odds!! No need for an an intake fan with this method. Just PVC and ratchet ropes. Never tried it so dont know how effective it is.
https://www.cocoforcannabis.com/how-...om-sucking-in/

I clicked on the link...looks doable. Thx for the tip!

[Tersky]

Np! I thought it was funny that i just happened across this exact topic and then read your post. I'd be curious to know how it works out if you try it!