Odor from the grow room when your cannabis plants are flowering can start to linger throughout your whole house.
The grow room smell of dank marijuana may not be welcoming to incoming guests to your house.
Or even outside the home the smell can be found if not properly contained.
When protecting your garden, odor control is essential.
Although some growers don’t mind the aroma of marijuana to fill up the house.
Some are more private, have a lot of visitors, are growing medical marijuana.
In this post, it will cover all types of odor control systems for growing marijuana indoors.
I will also include installation and types of fans required to clean the grow space and provide the simple formula to calculate your requirements.
It’s always good to have more than enough cubic feet to clear the area and a bit more to spare just in case you want to expand.
Grow Room Odor Removal
There are a few ways to eliminate scent of marijuana.
They are using an activated carbon filter or carbon scrubber with an inline fan, odor cover-ups, and (not recommended) ozone generators.
Carbon filters / scrubber
When needing to get rid of the smell from your grow room or tent carbon filters are the way to go.
The filters are the most environmentally safe and are currently the best at eliminating the awesome smell from your room or grow space.
Most carbon filters come in a wide range of sizes ranging from 4 -12 inches in circumference. They work in part with inline fans.
The best way to find out what size of carbon filter and fans are required for your grow space is to determine the cubic feet of your grow space.
So here is how you determine the size required with a simple math equation that goes like this:
Measure the length of growing space. The width and height and then multiply them, for example; a 4×4 grow tent.4x4x6.5=104 CFM
There are numerous ones on the market ranging from the low end to the high end.
The average carbon filter will work and depend on your budget, usually, the more you spend, the longer they last because they use better quality parts.
Here is a list of carbon filter sizes with the average cubic feet per minute (CFM):
- 4 inch carbon filter with a 260 CFM max
- 6 inch carbon filter with a 530 CFM max
- 8 inch carbon filter with a 780 CFM max
- 10 inch carbon filter with a 860 CFM max
- 12 inch carbon filter with a 1765 CFM max
Top Carbon Filter Brands
The top manufacturers of carbon filters and the most sought after are:
PHAT carbon filters they are just that (fat). The filters have over 2 inches of carbon and more holes than the average carbon filter.
Which means it can move a lot more volume air.
Green Gator carbon filters are exactly how they sound, Green, and are also not your average round filters.
They offer a unique size that is to reduce the airflow for more efficiency and they come in two sizes 8 inches and 6 inches.
Phresh carbon filters are one of the best on the market as they last twice as long as generic filters.
It uses carbon from an old coal deposit that is over 250 million years old. The carbon is some of the best in the world.
Check them out today if you’re serious on a long-lasting filter for the price.
Mountain Air carbon filters also use carbon that is very old. About 230 million years old.
This filter is said to last incredibly long over a three-year period, has excellent airflow and also reduces the noise of the fan.
The mountain air filter is well-liked and often sold out.
If you want to know more you should check out our review on Carbon Filters.
DIY carbon filter
It is possible to make your own DIY carbon filter scrubber, for small spaces such as micro grows, small tents or grow areas smaller than a 3X3.
Here is a short video on how to make your own, but you may just find a small 4 inch carbon filter on Amazon for the same price is costs to make one, unless you have some of the material noted in the video.
Check out the video on a DIY carbon filter,
Fans are essential when using a carbon filter.
For the proper fan to clean the room or tent it will be determined by the cubic feet per minute.
The same as the filter which makes it pretty easy to select.
Inline fans also come in various sizes, price ranges, and noise levels.
Usually the lower end is noisier than a more expensive one.
You will also have to determine the size of fan you require to match it up with your filter.
They are all measured in cubic feet per minute the same as the carbon filters above so use this simple math equation to figure it out
Measure the length of growing space the width and height then multiply them, for example; a 4×4 grow tent.4x4x6.5=104 CFM
- 4 inch inline fan with a 260 CFM max
- 6 inch inline fan with a 530 CFM max
- 8 inch inline fan with a 780 CFM max
- 10 inch inline fan with a 860 CFM max
- 12 inch inline fan with a 1765 CFM max
Some top manufacturer of inline fans are :
Hurricane Fans are great inline fans and they also make great wall mount fans fro the grow room or tent.
The fans are very popular among growers and are available on Amazon or at your local grow stores.
Hurricane fans come with an 8 foot power cord , available in an assortment of sizes.
Atmosphere vortex fans are a very expensive, they have a great energy efficiency and also are a lot quieter than your average fans out there.
So your do not need a cardboard box or duct silencer.
The unit comes with a variable speed controller which is great because in other brands it is not included.
How to set up a carbon filter with inline fan
There are many ways to setup your carbon filter to your inline fan here is one of the ways in this short video,
Below the diagram show the different ways to use your carbon filter with inline fan
There are two ways to use a carbon filter with an inline fan.
One way is to have air blown into the filter. Another way is to suck air through the carbon filter.
When trying to cover up the scent of marijuana, there is one company called ONA that is the most recommended brand at neutralizing the odor of cannabis.
Ona products included gels, sprays, and blocks.
These products should never be used in the actual grow space it’s best to use them outside the grow room or tent.
This is because your marijuana plants will absorb the smell from the ONA products you are using.
Most will put this on their exhaust hose if not using a carbon filter as a cheaper method.
Or some will use it in part with a carbon filter to make certain no smell is being carried out.
Ona Gel comes in a container with an open and close lid, so you can use only what you need.
There are different types available such as :
My favorite when the parents or neighbors are stopping by:
If you are wondering how long does ona gel last, it will usually last at least a month depending on use.
Surface and Air Purifiers
I use an air purifier in my house, the Oreck Proshield Plus.
This air purifier is easy to clean and works fantastic for allergies and dust from the air.
A long time ago I was tempted to use only this, but after doing some more research.
I realized that Air Purifiers are not good at removing the smell of marijuana from your grow room or grow tent.
They do an excellent job to get rid of the smell of fish , but flowering cannabis is another story.
So, air purifiers are not recommended
Ozone generators are an older technology for removing odor, which they do a great job at.
When no other living being is in the room.
They are not safe for humans or animals to be around.
Ozone generators are also banned because they are bad for the environment.
It is possible to use when you’re venting your smell into a closed room where the ozone generator is.
This was done back in the day and not used anymore. Or should not be used.
For proper grow room odor control system it is highly recommended to use a carbon filter with an inline fan.
These are hands down the best way to get rid of the smell from the grow room or tent.
The carbon filter and fan make a good ventilation system to control odors.
I will usually follow it up by using some ONA gel at times when I have company.
When the smell of cannabis is just that stinky, I need the extra protection.
Always remember to use Ona outside the grow area.
I have not made my own DIY carbon filter.
Never really had the urge and just got a 4-inch carbon filter instead and spent the money to save the hassle of the mess.
Just in case I spilled the activated carbon all over the place.
Do you use carbon filters?
Have you ever had an issue when the carbon scrubbers stop working and was it too late?
Let me know in the comments your experience with hiding the smell of your flowering cannabis.
Keep Growing my friends