Need some help with fan set up!!

Hi RIU,

So I recently got a pair of air cooled hoods and a new tent to veg in. Its 4 x 3 (ft) approximately.

The thing is I have one 6" Fan & Filter and I have a small TT fan running at about 180CFM.

I can purchase a new 4" rhino fan 260 CFM if necessary.

ATM I have it set up like this.

6" Filter - - - > 6" Fan - - - > AC HOOD 1 ---- > AC HOOD 2 ---- > T ----> Out

The T has the TT fan Extracting from the Veg Tent connected to it. UNFILTERED.

The problem is I don't have negative pressure in either of my tents so I am thinking this set up is incorrrect. The first tent is 4 x 4 (ft).

Also the second tent is extracting unfiltered air which is bad as I need complete stealth.

One suggestion I have had is to duct the veg tent into the flower tent as an intake.

Another is to have the CF in a box with the fan connected pulling from both tents simultaneously.

The issue is with my hoods and also I am running out of holes in the tents to run ducting out of.

Please guys any help is much appreciated. Need to solve this ASAP!

Thank You

I wouldn't duct the veg tent air from the cool tube into your flower room. if you need to go that kid of route, then go from the flower room into the veg room. I had 2 rooms/tents in the past, each having a 600w cool tube. I ran each cool tube on its own 420cfm fan and exited it into the basement. now I run a different set up (basically a trial setup at the moment. this is my current setup: flower tent (5x10x6.5) carbon scrubber-6" 420cfm fan-duct-600w cool tube-duct-600w cool tube-duct-tent-duct-veg tent (4x4x6.5)-duct-600w cool tube-duct-tent-duct 8" 720 cfm-duct into basement. now I haven't fired up my other 600w in flower room yet, waiting for my current 5 plants to finish up. but I don't see any issues with my new setup.

So you have two fans in that series. One pulling from filter in flower tent and pushing into the AC hoods and another fan connected pulling this air out?

I was going to duct the unfiltered air into the flower tent. NOT the light as this is already set up.

if it was me I wouldn't bother with a filter for the Veg tent and just use the 4" ventilation in there so I could use the 6" on the cool hood, and I would use it to pull air trough the hood from the filter (filter - ducting - hood - ducting - ventilation - out)





cool hood need to be between filter and ventilation and then just open/close the passive intake holes in the bottom of the tent to keep a bit of negative/under pressure (tent being pulled in a inch or so when zipping it up) normally 2-3x the size of the ventilation depending on how strong it is and if you got a filter on etc)

Slipon said:

if it was me I wouldn't bother with a filter for the Veg tent and just use the 4" ventilation in there so I could use the 6" on the cool hood, and I would use it to pull air trough the hood from the filter (filter - ducting - hood - ducting - ventilation - out)


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cool hood need to be between filter and ventilation and then just open/close the passive intake holes in the bottom of the tent to keep a bit of negative/under pressure (tent being pulled in a inch or so when zipping it up) normally 2-3x the size of the ventilation depending on how strong it is and if you got a filter on etc)

Click to expand...

Thanks mate but I have two air cooled hoods, one in each tent. I'm pushing at the moment but I am thinking of changing it so I pull out the one and push through the second hood.

Then I would for sure add a ventilation on each hood, and make em pull air

And I would use the filter and the strong ventilation in the flowering tent (IME Veg plant really don't smell much) if its still a concern a small filter more for the 4" or maybe just a jar of ona Gel would do the trick

A 4" ventilation should also pull about the same as a 6" with a filter on so Im sure they would exchanges the air at around the same rate

Ok so 2 separate fans and use the exhaust from veg into flower and let that scrub and take air out?

that could maybe work, need to adjust the intake so the 6" can handle the 4" and make under pressure with a filter on

if your putting hot cool tube air from the veg room and dumping into the flower tent area, your gonna dump in unneeded hot air into the flower room. that room will already be running hotter than veg and the hps runs ALOT hotter than a mh bulb. and yes I run 2 fans I series. the 6" 440cfm is directly mounted to my scrubber, then thru a lot of ductwork and thru 3 xxl cool tube hoods, then out my veg tent and an 8" 720 cfm fan helping pull the hot cool tube air and my flower room air out into the basement. I also have an 8" 320 cfm fan for my flower room intake fan, and 2 18" round oscillating fans blowing on the underside of the xxxl hoods in the flower room to get rid of the hot pocket of air that radiates from the xxxl hoods. I also run an 8000btu portable a/c unit during summer 12/12. I run a consistent 73/73 lights on lights off temps in flower.

ill try and get some pics after lights on at 7pm and post up for ya. its sometimes easier to visually see things vs reading/typing things out.

Always use ur fans to pull not push. They pull air more effectively than pushing it through. I would duct my lights together and just pull with my fan. If fans big enough u can cool 2-3 1k lights off it.

Everyone who is saying use your fan to pull air is correct minimally listen to that.

Sent from my SCH-I545

DemonTrich said:

if your putting hot cool tube air from the veg room and dumping into the flower tent area, your gonna dump in unneeded hot air into the flower room. that room will already be running hotter than veg and the hps runs ALOT hotter than a mh bulb. and yes I run 2 fans I series. the 6" 440cfm is directly mounted to my scrubber, then thru a lot of ductwork and thru 3 xxl cool tube hoods, then out my veg tent and an 8" 720 cfm fan helping pull the hot cool tube air and my flower room air out into the basement. I also have an 8" 320 cfm fan for my flower room intake fan, and 2 18" round oscillating fans blowing on the underside of the xxxl hoods in the flower room to get rid of the hot pocket of air that radiates from the xxxl hoods. I also run an 8000btu portable a/c unit during summer 12/12. I run a consistent 73/73 lights on lights off temps in flower.

ill try and get some pics after lights on at 7pm and post up for ya. its sometimes easier to visually see things vs reading/typing things out.

Click to expand...

Thanks mate pics would be helpful but I think I get what you're saying. I would like an ac unit but the funds won't allow for that yet. One day!

I definitely am getting the jist of your setup. I cant get an 8" fan but maybe I can use the TT fan as I currently have but vent the smelly air into the flower tent by making a hole.

I'm not dumping hot air from the light hood but heat from the tent mainly.





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alwaysgreen420 said:

Always use ur fans to pull not push. They pull air more effectively than pushing it through. I would duct my lights together and just pull with my fan. If fans big enough u can cool 2-3 1k lights off it.

Everyone who is saying use your fan to pull air is correct minimally listen to that.

Sent from my SCH-I545

Click to expand...

Pull from filter and push through light or pull all the way?

At the moment I am pulling from filter and pushing through 2 hoods but no negative pressure.

Is this the reason? Will pulling all the way solve this?

Sent from my HTC One 802d using the ROLLITUP app.

newbie187 said:

Pull from filter and push through light or pull all the way?

At the moment I am pulling from filter and pushing through 2 hoods but no negative pressure.

Is this the reason? Will pulling all the way solve this?

Sent from my HTC One 802d using the ROLLITUP app.

Click to expand...

I pull all the way. Fan is closet to exit. Pull through filter and both hoods and exhaust.

Most these fans are stronger when they are pulling air.

Cool thing about ducting it's not hard to switch around. So give it a shot. If you don't like it or don't get results your looking for switch it back.



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