Super stealth growbox build / Best practices? / In need of direction

[jimpalabre]

Hey everyone. First post on the forum!

I have had some experience with growing autoflowers in the past, but always limited to growing them in fabrics pots in my garden. I'm now considering getting started on building my first stealth grow box and have been amassing information here and there, but I have a few specific questions I can't find an answer to easily.

I'd like to build a small grow box, to accommodate a single plant, that would be placed in my bedroom, tucked away in a recess that I'm using to store clothes as of now. I don't want anything too big. Something along the lines of repurposing an Ikea Eket Cabinet (35x35x70cm).

I would use a SCROG technique and lots of training to keep the plants as low and dense as possible.

I have some prerequisite that are non-negotiable:

- It has to be as silent as possible.
- It has to be as odorless as possible.

I was thinking of fitting a Mars Hydro TS600 or TS1000 in there. Also looking at going with a hydroponic system, but it's very hard to find relevant informations as to how to build a small hydroponic system.

I've seen some build where the air extraction system is tucked away in another compartment up top. Does this help with noise? How about lining the inside with soundproofing foam before adding mylar on top?

I couldn't find many informations on using 'mufflers' around the extract. I also thought about lining the holes reserved for intake with one of these very dense foam that are used under washing machines to keep them from passing vibrations to the floor.

I'm not in any rush and I would like to really implement as many quality ideas as possible to ensure I get the quiest and most optimized box. I would like to go DIY as much as can be.

Is there anyone on here who mastered the art of silent/odorless growboxes?

Thanks in advance!

 

[Creeperpark]

Mars Hydro TS600 or TS1000 is a good start in any garden. You would do much better to start with a peat substrate to work with at first. Starting with hydro can make it very difficult until you get dialed in.

Odors are not really a problem when you use a small tent. You can silence any fans after they are installed. Get your set up put together and post some photos as you go, and the other members will help you. You are on the right track friend. Thanks for posting and sharing your ideas.

 

[jimpalabre]

Hey, thanks for your answer Creeperpark!

Indeed, I decided against going hydro. I'm going to go with what I know already, soil. I was thinking maybe coco, but I'll have to dig deeper into that, and that's for when the cabinet's ready anyway, and I'm far from that!

Here's a very rough first take on the cabinet. I'll be repurposing an Ikea cabinet to save up on building material. I am very open to criticism, as I have very little idea what I'm doing for now.

I have added measurements on the drawing and tried converting them to american units, sorry for any mistakes in that area, never was good at conversion when I was still in school aha.

1) I'm thinking of getting a Migro Array 2 as my light. It is fairly cheap and seems to be way more capable than a Mars Hydro. I'm trying not to cut corners on lighting. I guess it will make a difference? It's a measly 50$ more than a Mars Hydro TS1000 anyway. It's also more compact.

2) I left a space to house the ducts and carbon filter, but it's a little random at the moment as I don't know what I'm going to have to fit in there to ensure zero smell and minimal noise.

3) I've been looking at fans all day but I still can't really figure out what a growbox this size is going to require. The grow area is about 0.3-ish cubic meter. That shouldn't require much, right? I was thinking of maybe going with two stacked Noctua PC fans, but is it even able to pull enough to go through a filter?

4) I went a bit overboard placing a 5 gallons Air Pot in my sketch. I intend on growing autoflowers and would like to maximize yield, but a big pot like that will take a lot of space, and I'm afraid the plant will get out of control and get too close to the lamp. Even with proper LST/SCROGing.

5) I didn't place any air intake yet. I guess it'll be placed on the bottom of the wall opposite the extracting hole, also with a small-ish PC fan. Still trying to go as silent as possible, so I don't really know how I'm going to work that in yet.

Sorry for the long post! I still have a looooong way to go to build a nice setup that's going to give me nice, quality plants.

Any advice is more than welcome!

 

[goingrey]

That is quite near the size of the small tents Iike Homebox XS or Secret Jardin DS60, don't think those PC fans will provide adequate air exchange at all, let alone through a scrubber. You need a proper extractor fan. Moving air makes noise no matter how quiet the fan's motor is. Mufflers do work but are big, bigger than the scrubber. Intake can be passive.

 

[smirnoff420]

You need a large EC fan that can move a lot more air than you need and dim it down to 20-30%. Will be quite expensive, like 300 EUR or so and probably not fit in your upper compartment. Cheaper, but louder would be PC fans, Arctic P14 or P12 or similar, two or three of those in series, dimmed with one of those adjustable 5V-15V power supplies.

Carbon filter and hoses with 160mm diameter or larger. Sonodec (or other acoustically dampening) hoses. Maybe a meter or so of hose run after the fan, the longer the better.

Fans must be mounted using rubberbands or other similar method to mechanically decouple them from everything else to stop sound transferring through vibrations.

Fan on air intake is not good in my opinion, it will either push too much and reduce the negative pressure in the cabinet or won't help or even lower overall airflow. Also more noise.

For a fan blowing over the canopy a single very slow turning 12 or 14cm PC fan is fine and basically inaudible.

 

[jimpalabre]

You need a large EC fan that can move a lot more air than you need and dim it down to 20-30%. Will be quite expensive, like 300 EUR or so and probably not fit in your upper compartment. Cheaper, but louder would be PC fans, Arctic P14 or P12 or similar, two or three of those in series, dimmed with one of those adjustable 5V-15V power supplies.

When you say 'in series', what do you mean exactly? Stacked on top of each other and fitted inside of the hose?

I'm still having a hard time picturing how it would all come together / what it would look like once inside the compartment.

 

[smirnoff420]

Not stacked directly onto each other (that would reduce airflow and make them louder) but spaced apart. Rule of thumb is atleast the diameter of the fan between them.

Like this:
carbonfilter - fan - 12cm of hose - fan - 1m of hose.

 

[smirnoff420]

For explanation: Those PC fans don't lack airflow, they lack static pressure, which is needed for pulling air through filters with high resistance (like carbon filters).

Putting more in series helps with that as static pressure adds up when in series (while putting them in parallel would add up airflow).

When you go the PC fan route make sure you choose ones optimized for static pressure (like Arctic P series, F series would be optimized for air flow, good for canopy fan).

 

[jimpalabre]

Noted, thanks a lot!

I might need to lower my whole expectations. I just want to set up a small, cheap-ish, efficient & stealthy microgrow to experiment with LEDs / proper lighting for the first time. I wanted to keep in my bedroom and make sure I get zero smell from the whole operation...

I'll keep thinking about it. In the meantime, all of these answers really help!

 

[jimpalabre]

Not stacked directly onto each other (that would reduce airflow and make them louder) but spaced apart. Rule of thumb is atleast the diameter of the fan between them.

Like this:
carbonfilter - fan - 12cm of hose - fan - 1m of hose.

I made a very rough first model of what it *could* look like.

I'm thinking two Arctic Bionix P120 (68CFM) or P140 (74CFM) in series, spaced apart, either in a custom 3D printed housing, or just hooked with a length of insulated duct.

I'm just trying to see how everything would fit in there. It's hard picking a carbon filter given my size constraints. I also have the duct make a U-turn straight after the fan to give it some length while maximizing space for the plants... But I'm pretty sure that's a bad thing, right?

Any thoughts?

 

[jimpalabre]

Another question. Can I get away with not using any duct at all? Carbon filter hooked straight to the fan in series, with the fans housed in a soundproofed box? I saw another DIYer on there that used PC fans and zero ducts for a 2 plant grow and reported no smell.

 

[sublingual]

Yeah, that's what you want now but later you will outgrow that small space. ACinfinity makes quiet fans for exhaust and circulation and I am pleased with them. If you are going to grow a plant, you should do it right or not at all. You can always just buy what someone else grew with experience and not grow yourself. For your grow to be smell and sound proof will require a lot of ingenious tinkering in the space you have described. Is it worth it? Will the plant have flexibility in that space?

 

[chilliwilli]

A friend of a friend always puts his fan on the end of the line and has it sitting on the tent, like carbon filter- hose - fan. This way is the lowest noise construction i have seen so far. The air moving in the hose also creates noise.
Imo there is no shortcut to use an overpowered and dimmed fan when it comes to noise reduction.

 

[smirnoff420]

Those newer Bionix Arctics look good from the specs, I'd go 2x 14cm.

The U-Turn is not ideal, but I think it shouldn't be too bad. You can also have the fans directly at the exit without hoses like in your latest drawing, it's just going to be louder. The meter of Sonodec ducting acts as a muffler for the fan noise (it is perforated on the inside, similar principle as in a car muffler).

Smell-wise there won't be a difference that depends solely on the quality of the filter. I use a small CAN filter Lite 150 for a similar size, but it's not 100% smell proof, with smelly plants when in flower and humidity gets too high I can smell a little sometimes (doesn't bother me though). But there are certainly better filters than those CAN Lite filters I just use them because I can get them locally cheap. Look for something with high CTC value, like CTC80.

When you put somerhing solid 3dprinted between the fans, make sure you don't build a loudspeaker accidently, maybe use TPU or something flexible. Or maybe just adaptors for a piece of hose 3d printed from TPU. Hoses are so soft they decouple very good.

Here is one of my cabinets, two Arctic P12 are above the top board where the lamps and filter is mounted to. Plus one blowing on the lamps to get the heat from the lamps down to the plant.

 

[jimpalabre]

I'm about to splurge and get a Secret Jardin extractor instead of tinkering endlessly. Does anyone have any experience with them?

Looking at the DF16E150 (the smallest one) that can do 50/100/150 m3/h. Sounds like even the smallest setting would work perfectly for my small box?

I'd also get one of their carbon filter. They look very high quality and are rated CT80, as you advised me... But since I really want the whole operation to be as odorless as possible, they offer a 100 m3/h version and a 150 m3/h version. So, more charcoal. I don't want to get something and realize it doesn't filter everything out...

 

[jimpalabre]

I can also go with something from Prima Klima... Still at a loss here.

I will be order from this website, so if anyone wants to have a look and advise me on something, it'd be greatly appreciated. I'm looking at staying around/under 150€.

Edit: I read in several places that Prima Klimas are loud asf and don't take low speed well at all. They start making a weird buzzing sound.

 

[jimpalabre]

Alright. Pulled the trigger on the smallest Jardin Secret extractor and their second smallest filter. Should do the trick nicely. I'll build a soundproofed box to house the fan.

I'll order the Migro Array 2 125W beginning of July and I'll get started with building the furniture! Exciting!

 

[sublingual]

Alright. Pulled the trigger on the smallest Jardin Secret extractor and their second smallest filter. Should do the trick nicely. I'll build a soundproofed box to house the fan.

I'll order the Migro Array 2 125W beginning of July and I'll get started with building the furniture! Exciting!

You are going for it, good for you. Welcome to agronomy.

 

[teide]

Good luck, keep us updated