0.2 Cubic Metre Stealth Tent Ventilation Question With Pics

Hi, everyone. I've been planning a super stealth tent (by necessity) and I'm unsure of a few things. I've grown before, years ago, (back when Grotrons were a thing) and a lot has changed. I was always ventilating then, but never had the need for sound or smell to be non existant, so I'm here to ask your advice on my proposed setup before I click the buy button on a bunch of stuff that I've hand-picked into a shopping cart from a hydro shop.

STEALTH IS IMPERATIVE, so please keep that in mind when offering suggestions. I'd rather overkill my purchase than to have a leaky system. (If this can be done without a $700 filter, etc, otherwise I'll scratch the whole plan).
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I'll be using:

Homebox HomeLab Indoor Portable GROW TENT - HL40 V2.0 | 0.4M x 0.4M x 1.2M


Inline Mixed Flow Tube Air FAN - 100MM (4" Inch) | 180CFM | 35W | 35DB


Black PVC Coated Dual Layer Air DUCT - 5 Meters | 102MM (4" Inch) | Ventilation


2x Original Phat Phresh Air Activated Carbon FILTERS - 100 x 300MM | 150CFM


Growlush Fan Adjustable SPEED CONTROLLER - Max 500W | 2.08A


Y Duct 3 WAY CONNECTOR - 4" x 4" x 4" (100MM) | Inline | Fan | Air Ventilation


MARS HYDRO LED Reflector 48 - True Watt 101W@220V | Epistar HI-LED 5W Chip


Odour Neutralising Agent (ONA) Pro Gel - [Size: 1L]

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I plan to grow Northern Lights as a test run on how filthy I think my buds could get without blowing its cover. Baby steps, for piece of mind.

I looked at silencers as well, but they don't seem to come in the 4" size, and the top exhaust hole in my tiny (0.2 cubic metres/ ~ 5 cubic feet) tent is maximum 5 inches, so will need a 4/6 reducer either side of it, to make use of larger ducting, filters and silencers (undesirable anyway, considering where I plan to run it, pictured below).

I've decided that I'm not going to worry about buying silencers just yet, as I've just bought a new pair of sheepskin boots (the real name for them is not allowed, ??? LOL) and the old ones look like pretty good silencers to me.

I'll let you know how they work.

Anyway, is this picture a stealthy looking thing to set up as far as smell and sound goes? I feel that the little 4" fan should cope alright dialed down, but what do you guys think? Will any silencing achieved behind the drawers become loud again when venting through a few drawers opened a cm or so? Also, I've split the ducting for two 100mm carbon filters and two exhaust lines, hoping that a dialed-down 4" fan would filter slowly and exhale gently and quiet, before being let out of multiple gaps in drawers as a (hopefully) gentle 'draught' in the room.

Please let me know the reality of my expectations.

Thanks, guys.

I apologize for the terrible drawing. I'm not bent. That's my finest work, to date.

Here's the picture:

Ozmap said:

Here's the picture:

Click to expand...

I think I would vent through top. Intake passively through drawers. No ducting through drawers though just an open intake in tent and let it suck from every crack/crevice.

Ozmap said:

Hi, everyone. I've been planning a super stealth tent (by necessity) and I'm unsure of a few things. I've grown before, years ago, (back when Grotrons were a thing) and a lot has changed. I was always ventilating then, but never had the need for sound or smell to be non existant, so I'm here to ask your advice on my proposed setup before I click the buy button on a bunch of stuff that I've hand-picked into a shopping cart from a hydro shop.

STEALTH IS IMPERATIVE, so please keep that in mind when offering suggestions. I'd rather overkill my purchase than to have a leaky system. (If this can be done without a $700 filter, etc, otherwise I'll scratch the whole plan).
------------------------------------------------------------------
I'll be using:

Homebox HomeLab Indoor Portable GROW TENT - HL40 V2.0 | 0.4M x 0.4M x 1.2M


Inline Mixed Flow Tube Air FAN - 100MM (4" Inch) | 180CFM | 35W | 35DB


Black PVC Coated Dual Layer Air DUCT - 5 Meters | 102MM (4" Inch) | Ventilation


2x Original Phat Phresh Air Activated Carbon FILTERS - 100 x 300MM | 150CFM


Growlush Fan Adjustable SPEED CONTROLLER - Max 500W | 2.08A


Y Duct 3 WAY CONNECTOR - 4" x 4" x 4" (100MM) | Inline | Fan | Air Ventilation


MARS HYDRO LED Reflector 48 - True Watt 101W@220V | Epistar HI-LED 5W Chip


Odour Neutralising Agent (ONA) Pro Gel - [Size: 1L]

------------------------------------------------------------------

I plan to grow Northern Lights as a test run on how filthy I think my buds could get without blowing its cover. Baby steps, for piece of mind.

I looked at silencers as well, but they don't seem to come in the 4" size, and the top exhaust hole in my tiny (0.2 cubic metres/ ~ 5 cubic feet) tent is maximum 5 inches, so will need a 4/6 reducer either side of it, to make use of larger ducting, filters and silencers (undesirable anyway, considering where I plan to run it, pictured below).

I've decided that I'm not going to worry about buying silencers just yet, as I've just bought a new pair of sheepskin boots (the real name for them is not allowed, ??? LOL) and the old ones look like pretty good silencers to me.

I'll let you know how they work.

Anyway, is this picture a stealthy looking thing to set up as far as smell and sound goes? I feel that the little 4" fan should cope alright dialed down, but what do you guys think? Will any silencing achieved behind the drawers become loud again when venting through a few drawers opened a cm or so? Also, I've split the ducting for two 100mm carbon filters and two exhaust lines, hoping that a dialed-down 4" fan would filter slowly and exhale gently and quiet, before being let out of multiple gaps in drawers as a (hopefully) gentle 'draught' in the room.

Please let me know the reality of my expectations.

Thanks, guys.

I apologize for the terrible drawing. I'm not bent. That's my finest work, to date.

Click to expand...

Also my biggest fear for u is that u want have the head space to get that light far enough from the plants

Jbird7 said:

Also my biggest fear for u is that u want have the head space to get that light far enough from the plants

Click to expand...

Thanks for the reply, Jbird7.

Yeah, the height is pretty restrictive, but as stealth is my concern, the cupboard door that the tent is behind is the only spot that hides itself from the room entrance, even if the door next to it, is open. The paired doors are both 890mm space each x 600mm deep, so that decided my tiny tent size. I've got enough senses to fool, so I wasn't going to compromise on anything that I could 100% hide, and that size is the only one that doesn't get seen. It decided everything from then on.

I plan on tying down as much as possible, to make this space usable as it is that size, or nothing.

The far left cupboard would fit a 600x600 or an 800x800 in there, but it ups the risk for me as far as being seen and having to move more air, etc. I decided on 'safe' sizes and worked from there, trying hard not to be greedy about it. I'm in Australia and while I don't know the weed laws here, If I had an 800x800 space, I would use it. I know that years ago, we had cops come around for something unrelated, they spotted a dozen plants in the back yard and said, "You're lucky that you only have two plants growing, otherwise I'd have to charge you for dealing. I'll be back in a minute." We all took the hint and grabbed a pair of pots each and hid them inside. He came back and gave us a fine for two plants. Must be more paperwork than it's worth, haha.

But bac to what I was saying:

With my 400x400 space, if I ever have the misfortune of having the fuzz wander in again, at least 'Exhibit A' would be an over-sized duffle-bag with a light in it, and not a room full of stuff that they'll try to call me a drug-dealer over. That's my logic, anyway. A single plant incapable of reaching full height is probably just a fine, and my money is worth way less to me, than my time is.

As an extra precaution, I did splash out and replace any ducting in the picture (that is outside the tent) to 150mm (6") as well as the fan which is now a 300-and something cfm. I really hope that it will be a better choice, because I was happy with the 100mm (4") but thought, "Once this thing gets tall in here, (200mm ), it's probably going to get a little warmer and by then it will also be my Summer). I hope that my speed controller can tiny down the 150 mm fan a lot, so that my plant stays on the ground, not uprooted and stuck to my filters.

I'll be focusing on tied-down short plants with short harvest time and half-decent yields, but low odour is my main concern, so I'll have a crack at Northern Lights, just to see whether my preferences will be possible with my setup and circumstances.

I ended up with:

Peyote Critical
Pink Kush
Blueberry OG
Cookies Kush

...as strains that met all of my other requirements, (I spreadsheeted Barneys catalogue)

I'm thinking that they stink a bit more, but I'll see.

What I really want, is 8 Ball Kush and Blue Cheese, but for whatever reason, they unfortunately didn't make the short list. Maybe I'll have a look and see how short they fell from requirements. Maybe I could make an exception.

Jbird7 said:

I think I would vent through top. Intake passively through drawers. No ducting through drawers though just an open intake in tent and let it suck from every crack/crevice.

Click to expand...

I like this Idea. Will no ducting add to the noise? Maybe i can run some flex through the bottom of a cardboard box, sitting on top of the cupboard, if it does. Your simple solution seems ideal, if I can get it quiet. I'll probably put a screw in each door to keep them slightly more slightly-ajar.

I probably should have waited for your reply (like I said I would) before pushing 'buy button' but I didn't. Oh well, I have some extra ducting and Y-pieces, haha.

Thanks for your help, it has been truly that.

Ozmap said:

Thanks for the reply, Jbird7.

Yeah, the height is pretty restrictive, but as stealth is my concern, the cupboard door that the tent is behind is the only spot that hides itself from the room entrance, even if the door next to it, is open. The paired doors are both 890mm space each x 600mm deep, so that decided my tiny tent size. I've got enough senses to fool, so I wasn't going to compromise on anything that I could 100% hide, and that size is the only one that doesn't get seen. It decided everything from then on.

I plan on tying down as much as possible, to make this space usable as it is that size, or nothing.

The far left cupboard would fit a 600x600 or an 800x800 in there, but it ups the risk for me as far as being seen and having to move more air, etc. I decided on 'safe' sizes and worked from there, trying hard not to be greedy about it. I'm in Australia and while I don't know the weed laws here, If I had an 800x800 space, I would use it. I know that years ago, we had cops come around for something unrelated, they spotted a dozen plants in the back yard and said, "You're lucky that you only have two plants growing, otherwise I'd have to charge you for dealing. I'll be back in a minute." We all took the hint and grabbed a pair of pots each and hid them inside. He came back and gave us a fine for two plants. Must be more paperwork than it's worth, haha.

But bac to what I was saying:

With my 400x400 space, if I ever have the misfortune of having the fuzz wander in again, at least 'Exhibit A' would be an over-sized duffle-bag with a light in it, and not a room full of stuff that they'll try to call me a drug-dealer over. That's my logic, anyway. A single plant incapable of reaching full height is probably just a fine, and my money is worth way less to me, than my time is.

As an extra precaution, I did splash out and replace any ducting in the picture (that is outside the tent) to 150mm (6") as well as the fan which is now a 300-and something cfm. I really hope that it will be a better choice, because I was happy with the 100mm (4") but thought, "Once this thing gets tall in here, (200mm ), it's probably going to get a little warmer and by then it will also be my Summer). I hope that my speed controller can tiny down the 150 mm fan a lot, so that my plant stays on the ground, not uprooted and stuck to my filters.

I'll be focusing on tied-down short plants with short harvest time and half-decent yields, but low odour is my main concern, so I'll have a crack at Northern Lights, just to see whether my preferences will be possible with my setup and circumstances.

I ended up with:

Peyote Critical
Pink Kush
Blueberry OG
Cookies Kush

...as strains that met all of my other requirements, (I spreadsheeted Barneys catalogue)

I'm thinking that they stink a bit more, but I'll see.

What I really want, is 8 Ball Kush and Blue Cheese, n, they unfortunately didn't make the short list. Maybe I'll have a look and see how shor


I like this Idea. Will no ducting add to the noise? Maybe i can run some flex through the bottom of a cardboard box, sitting on top of the cupboard, if it does. Your simple solution seems ideal, if I can get it quiet. I'll probably put a screw in each door to keep them slightly more slightly-ajar.

I probably should have waited for your reply (like I said I would) before pushing 'buy button' but I didn't. Oh well, I have some extra ducting and Y-pieces, haha.

Thanks for your help, it has been truly that.

Click to expand...

Hey sorry been busy... Sounds good... Honestly i think a 6" is probably overkill... And i doubt youd have to leave the door ajar..wldnt that defeat the point of hiding it so well..are u gonna have the doors open most of the time and closed wen necessary? Im sure it can intake through all the tiny openings in th cabinet.. Any updates?

Hi, Jbird. When you say overkill for the 6" fan, do you think that even slowed down it will be too much for the space and filters to be useful? ...or just that I could have saved some money by buying the 4" fan? I'd rather the 4" and it probably isn't too late to change my order as they called me yesterday about it being delayed.

I won't be having cupboard doors open at all. I measured the air-leak gaps in the cupboard and worked out that the area of 6" suction would need the gap in the doors to be a mm or 2 larger thinking that if I didn't match the suction area, the doors might rattle or something. Not sure, I'll have a play when my stuff arrives.

My only update is that my shipment is a couple of weeks away due to backordering things that I wasn't prepared to settle for something else. The Phresh filters being one of the delays.

Do you think that I should change my order back to a 4" fan or will the 6" be useful turned down? 4" acoustic ducting was not available at that shop.

Thanks for your help, Jbird.

Depends how many cfms ur fan is and the size of ur intakes. With most fans that are 6 inches, when turned all the way down, still crank like 300 cfms i believe. At that speed u wld want ur intake to be about 3-3.5×the size of ur outtake. Otherwise youll collapse the tent or at least have it sucked in limiting ur space even further. I woul definitely get a smaller fan and do 4 ".

Could u cut a hole in the backand move it off the wall an inch or even less?

Thanks, Jbird. I'll change my order.

Jbird7 said:

Could u cut a hole in the backand move it off the wall an inch or even less?

Click to expand...

Yeah, the back is just stapled and easy enough to push out.

Bugger. looks like they've shipped the part of the order that isn't being backordered. Oh, well. I'll see what rocks up.

Jbird7 said:

Depends how many cfms ur fan is and the size of ur intakes. With most fans that are 6 inches, when turned all the way down, still crank like 300 cfms i believe. At that speed u wld want ur intake to be about 3-3.5×the size of ur outtake. Otherwise youll collapse the tent or at least have it sucked in limiting ur space even further. I woul definitely get a smaller fan and do 4 ".

Click to expand...

I just double checked and the intake flaps combined (2) look to be about the same square area of the floor. ~200 x 400mm each. Might save me, but I'll get a smaller fan anyway. I didn't realize than a speed controller wouldn't be able to do trickle mode, haha.

Thanks, Jbird.

An update:

My stuff arrived today, except for the backordered tent, filters and light.
The 6" fan is massive, I don't know what I was thinking when I changed to that from the 4".
I'm going to order a 4" because while the speed controller can do a trickle of a breeze, it has a bit of a hum to it. I have read a few ways to quieten it that I haven't tried yet, so I'll have a play around with it.

The performance of it is useful (high and low speed) but its size and more importantly its noise are my concern with it.

Do you think the 4" will be any quieter? I bought the 6" thinking from what I've read, that a larger fan can be ran quieter than a smaller fan. I'm guessing that the comparison is a small fan on high vs a larger fan on low?

I don't need the top 90% of the 6" fan or the top 75% of the 4" fan. (just guessing %).

Will a 'trickling' 4" be quieter than a trickling 6"? I guess that is what I needed to know before I bought anything.

Thanks for any input.

The 4 will be much quieter, and with a fan speed controller you could quiet it down.

Edit: Be sure to have enough fan speed to activate the filters.

Awesome. Thanks, Gram Reaper.

Now I'll have an extraction fan AND an air conditioner for the shed, in Summer.

Here's what I just bought to replace the 6". I think I'm going to need a plug-converter, though. The reviews of this seem pretty decent but a bit mixed. If this can't be run quietly, then I'll give up and just swap the lot, for a bag of weed. Paid way more than I wanted to for it, but what can you do? They don't have them in my country, it seems.






As the Gram Reaper says, the airflow for the filters seems to pop up and some people say they have plenty, some say no. As long as it can move 10 cubic feet through 4" filters, I'll be happy. I saw Renfro tell someone in another thread that filtering is the tradeoff for silence. I only want to use a small amount of this fans capabilities, so I'll be majorly pissed if I have to upgrade this one, as well.

Maybe the end of this thread will turn into a garage sale of brand new fans. Tested once, brand new in box, a few tear-stains on box but doesn't affect the fans function.