posative vs negative pressure in grow tents?

[GET MO]

Im sure no pressure is the best way, but thats not whats going down. So should I have the tent being pushed out by air coming in or sucked in from air blowing out? or does it make a difference? Wondering as far as the tents holding up with light leaks n al that and if it makes any difference for the plants. Thanks yall.

 

[Jellyfish]

So should I have the tent being pushed out by air coming in or sucked in from air blowing out?

I believe you want the latter. Read the thread, Ventilation 101 for more help.

 

[sneaky101]

Grow tents have tiny holes in them that will allow the smell to escape. You want it to be sucking in, not out. Granted you will loose sq footage, but better to not let the smell out. If it is pushing the walls out, it will be pushing air out that has not been scrubbed.

 

[GET MO]

thanks yall, sneaky101 thats a good point right ther, Im not worried about smell but if i was that would be it.

 

[PoopyTeaBags]

sucked in with a carbon filter will make it so you can smell if it pushes out carbon filter or no itll smell...

 

[megayields]

POSITIVE words are POWERFUL!

 

[FreezerBoy]

Im sure no pressure is the best way

No, no, no, no, no. Did I say no? I meant no. Anyway, no.

Negative pressure or bust (as in busted and carted away to jail) Negative Pressure for Dummies

 

[bobblehead]

lol... Dude's not worried about smell... So there is no scrubber. Imo, negative pressure is the way to go. An extraction fan at the top of the room will pull the heat up and away from the plants. If you need more cooling, add an intake fan. I run 2 435cfm fans, 1 intake 1 exhaust and I scrub the lung room.

 

[opt1c]

i've found that a 6" exhaust fan set to a thermostat with a 4" intake fan on 24/7 is great for 4x8 and 8x8 tents... for 4x4 tents an exhaust fan set to a thermostat and 4" ducting on all openings long enough to be light proof is the best bet... i've found that you can damn near rip a tent apart from too much negative pressure and that they last a lot longer when you have it a tad more equalized

i always run a free standing cf filter in any room i have a tent in as the tent will be exchanging the air in that room in and out of the tent constantly to keep temps in check inside the tent.... nice thing is that you can have multiple tents and just one cf filter

 

[FreezerBoy]

lol... Dude's not worried about smell... So there is no scrubber. Imo, negative pressure is the way to go. An extraction fan at the top of the room will pull the heat up and away from the plants. If you need more cooling, add an intake fan. I run 2 435cfm fans, 1 intake 1 exhaust and I scrub the lung room.

Anyone not interested in controlling smell may well be putting their lives on the line. People get killed over this stuff. Killed as in dead, muerte, food for worms, sleeps with the fishes, dead.

Intake fans are the fastest, easiest and only way to achieve positive pressure. Positive pressure insures stench. Safety says: no tell, no smell, no sell. Smelling is worse than telling, it's advertising. It's begging for trouble. Leave intake fans for experts. Better to open another passive intake and/or a larger fan.

 

[bobblehead]

Anyone not interested in controlling smell may well be putting their lives on the line. People get killed over this stuff. Killed as in dead, muerte, food for worms, sleeps with the fishes, dead.

Intake fans are the fastest, easiest and only way to achieve positive pressure. Positive pressure insures stench. Safety says: no tell, no smell, no sell. Smelling is worse than telling, it's advertising. It's begging for trouble. Leave intake fans for experts. Better to open another passive intake and/or a larger fan.

calm down bro... Lol... I don't have a smelly grow myself... But some people really don't need to be concerned. In cali the market is so flooded and it seems like there's more people who grow than don't... Some of the big canadian growers aren't concerned w/ their federal med program...

just saying... For most of us, negative pressure w/ a scrubber is a must. I don't think that's the case with the op.

 

[GET MO]

Thanks yall, appreciate all the answers, Ima have fan suckin through the light an out the tent, then probly another tube goin in from out the window on the bottom to get that good fresh air. Where I be smell is of no concern, Im in the boonies yo. everyyear damn near the whole town reeks of bud. Same with my block tho when I lived in sactown.

 

[sso]

the greater the negative pressure the greater the stress on the fan. (and the fan gets louder as well)

i try to keep the negative pressure at an absolute minimum. (it still works as it should)

 

[FreezerBoy]

calm down bro... Lol... I don't have a smelly grow myself... But some people really don't need to be concerned. In cali the market is so flooded and it seems like there's more people who grow than don't...

Plenty of time to be calm after your dead. A 3 second Google search shows the following on the first page alone. Imagine how many hundreds, perhaps thousands of examples are found on pages 2 and beyond

Grower killed in Amador County medical pot shootout

Medical marijuana growers concerned following homicide

Marijuana grower found dead

Medical marijuana grower shoots, kills robbery suspect

Homicide Raises Concerns Among Medical Marijuana Growers

A rec card may help in court (I wouldn't bet on it) but, provides no protection on the street. It won't stop a cop and it sure as heck wont stop a bullet.

 

[ThePizzaMan]

Negative pressure. You want the walls to suck in slightly..or if you are running a 6" or 8" fan...your walls will be bowing in. This is what you want. You do not necessarily need a dedicated or (active) intake..but the air that is drawn through the side vents of the tent should be plenty of fresh air for your intake(passive).

 

[Phaeton]

I'm a hermit living way out of town. I got a visit from a gang representative offering to be the exclusive vendor for my product.

This guy kept it friendly but it does seem straightforward, if they can sniff you out they want a piece. Best to avoid notice in the first place, it is not the police that will hurt you. The police just fuck up the rest of your life for you.

 

[RidgeRebel]

filtered air blowing in will keep the molds out. standard lab procedure is to pressurize @7 psi, it doesn't take much. grocery stores do it like that too . but for heat, sucking that shit out will work most efficiently, the faster the better. passive intakes should be twice as big as the exhaust for optimum flow.

 

[Kcar]

http://www.hydrogardencenter.com/ductfanspeedadjuster.aspx
These make it easy to balance pressure...

 

[RidgeRebel]

oh those fan speed controllers can be found a harbor freight also, for like $12.99. labeled as variable speed controllers, they are literally the exact same thing. literally.

 

[DocGreenthumbs]

Freezer Boy you seem to be slightly paranoid. Keep in mind, some of us live in remote areas where smell isnt an issue for one or possibly MANY reasons. Some reasons out of endless possible reasons for not bn concerned about odor would be if you live in BF Nowhere, no neighbors for many miles, only growing a small number of plants, other odors in the area cover up the smell from the cannabis(farm animals etc), its a legal grow, you have your home and property secure. The poster was asking a question and hoping to hear some helpful advice or tips. No garden or gardener is the same. If hes not concerned with odor, he has his reasons and most likely was looking to hear anything other than the fact that he die lmao if his pot grow smells like pot. Maybe you live in Compton or are neighbors with Mexican Drug Cartels or something and thats why you fear for your life lol. But for this thread and info, research VPD theres some interesting reading there. But yes, negative pressure is the prefered choice for the majority of gardeners.(The ones that havent lost their lives to smelly gardens of course)