Sweet, fruity, minty, skunky — the aroma of cannabis plants is a key feature of every crop, as it’s frequently the first hint of the characteristics and quality. The odor of cannabis comes from compounds called terpenes.
While these oil-producing compounds are essential for the plants, they make a loathsome challenge for cannabis growers. This is especially true when you grow cannabis in an urban area.
Aside from the cannabis odor itself, there are also distinguished smells that come from supplements such as pesticides, fertilizers, and dung. When all these smells get mixed up, you get an unpleasant odor that lingers inside your grow room.
That raises the question: How to get rid of this stench?
There are different odor control strategies that can address this issue, including sealed greenhouses, odor neutralizers, ozone generators, and biofilters.
However, it turned out that charcoal filters ( aka carbon filters or carbon scrubbers) can eliminate this pesky odor most effectively. In this article, we will present you the top 5 charcoal filters on the market.
5 Best Charcoal Filters for Grow Rooms
1. VIVOSUN 4-Inch Air Carbon Filter Odor Control – Best Four Inch Filter
Offering everything you will ever need to eliminate the most undesirable odors from your grow room or tent, this four-inch filter by VIVOSUN provides ultimate air filtering. In essence, this is an aluminum-framed premium charcoal with a carbon pad. That machined-packed carbon contributes to a high efficiency. In addition to the carbon filter, you also get carbon filter belts and a pre-filter.
Something that’s definitely worth mentioning is that this VIVOSUN filter uses top-grade Australian virgin carbon is 1050+ RC48 rated. We especially like its prominent area between inner and external mesh that improves air flow. It provides a 53-percent open area.
You can be sure that it will serve you for two years or so thanks to the reversible Base-Flange design. The filter flanges can easily swap so that the product doubles as an exhaust filter and intake filter. They are changeable, meaning you will be able to replace it when needed without having to purchase a new carbon filter. Though, it’s recommended to replace the filter after 1 year to maximize effectiveness.
This charcoal filter is a great choice for smaller grow ops and it’s perfect for cabinets, grow tents, cupboards. It can also be used for lower-level floors, air-cooled lighting, and window-to-window ventilation.
- Effective odor control
- Machine-packed Australian virgin carbon
- Inner and outer mesh
- Switchable filter flanges
- Sleek design
- When aluminum frame bent, it doesn’t fit into ducting
- Low capacity – not suited for larger grow ops
2. Think Crucial Carbon Filter & Odor Control – Best Six Inch Filter
If you are searching for a carbon scrubber that can handle a medium to large grow op, then your safe bet is to buy a larger filter that can fit a 6-inch inline fan along with ducting. Our recommendation is the 6″x16″ odor control carbon filter by Think Crucial. And here’s why.
Designed to last up to 18 months, this heavy-duty carbon filter is truly built to last. You can use it to remove odors from your bloom room, grow room, drying room, or any other indoor area. It features a CFM 400 rating, which means that this professional grade filter sufficiently eliminates allergenic pollutants, dirty air, and foul odor emissions while filtering purified, fresh air at the same time.
So, you don’t have to struggle with ventilation anymore, as this filter will get the job done just fine. With this device, the days of unfiltered air that comes from your growing room are over!
- CFM 400 rated
- Professional design
- Easy to install
- Perfect air speed
- Relatively long lifespan
- Ducting sold separately
- No replaceable parts
3. TerraBloom Premium Carbon Filter – Best Eight Inch Filter
For extra large grow tents or grow rooms, it’s necessary to have a charcoal filter that’s both large and thick for enhanced air filtration. The Premium Carbon Filter from TerraBloom is a safe choice that fits the bill. It can be used in any professional-level grow op. However, bear in mind that you will need a strong fan for this filter. When used with an improper or weak fan, it doesn’t work well.
Compared to other economy grade odor control filters on the market, this device has a fairly thick carbon bed of 46 mm. That ensures a longer lifespan as well as better performances in getting rid of odor. This product is made of the top-grade RC-48 carbon, which is proven to effectively eliminate harmful pathogens and unpleasant smell in the indoor spots. With the extremely small carbon granules, the particles are deeply filtered which eventually results in a clean air.
Besides the filter, the package includes two pre-filters, pre-installed flange and base. The base and flange are made of aluminum for better resistance to corrosion and rusting. It also makes the setup easier.
- Top-grade virgin carbon used
- Extra thick carbon bed
- Deeply filters smell and odor
- Comes with machine washable pre-filters
- Very durable
- Long lasting
- Requires frequent maintenance
- No replaceable/removable parts
- No warranty
4. VIVOSUN 440 CFM Inline Duct Fan with Carbon Filter – Best Six-Inch Combination Deal
It’s sometimes more cost-effective to buy a carbon filter and inline fan at once as a combo package that purchasing them separately. If you need both, go for this filter and fan set by VIVOSUN. This combo pack is an excellent option for those who are seeking a good deal that’s reliable and high quality.
The 6-inch fan generates a speed of 2,450 rev/min, whereas the odor control filter consists of 1050+ RC48 Virgin Australian carbon bed. Note that the filter comes with the reversible flange as well as an outer and inner mesh to provide better airflow.
The pack also includes an instructional pamphlet and mounting brackets alike. Ducting and flange height are not included though.
- Both fan and filter included
- High-quality charcoal bed
- Increased air flow
- Decent fan speed
- Changeable Velcro pre-filter
- Cost-effective solution
- Filter pad isn’t internal
- No ducting
- No warranty
5. iPower 750 CFM Duct Inline Fan with Carbon Filter – Best Eight-Inch Combination Deal
The last product on our list but not least in importance is Combo for Grow Tent Ventilation by iPower. This package includes everything you could ever need to put together a heavy-duty ventilation system in a grow room. In fact, it consists of a carbon filter, duct inline fan, as well as 25 feet of ducting.
The 8-inch fan is made from top-quality 1050+IAV Australian carbon and it includes the best UL components to have a low noise level. Quiet operation is also ensured by a center hub and composite fan blades which cut down on noise and vibration. As for the ducting, it comes with two stainless clamps that allow you to attach this uninsulated aluminum ducting to the filter and fan. It implies corrosion resistant wire helix and flame retardant coating.
There’s also a pre-filter included to prevent dust from clogging the unit. It is recommended to replace this pre-filter every six months. Considering all these great things and features, it is easy to understand why this iPower combo is one of the best combination deals nowadays.
- Virgin Australian charcoal filter
- High-quality UL components
- Quiet-running fan
- All necessary equipment included
- Priced competitively
- Only two clamps included
- Flex pipe is too small
- There is no warranty
Things You Must Know Before Buying a Charcoal Filter
With the broad array of charcoal filters available today, it is difficult to find the right option that fits for purpose indeed. Only the best carbon filters can completely eliminate odor and harmful airborne pathogens. We will provide you with a complete guide consisting of essential considerations that will help you find an ideal filter for your needs.
One of the first things should take into consideration when shopping for a charcoal filter is its size. The carbon filter you choose must match all the components of your growing room in order to operate effectively. Thus, the lighting system, air conditioner or ventilation system and exhaust system require a particular size of the carbon filter. For example, if you use a 6-inch inline fan, you’ll also need a 6″ carbon filer for the best results.
Apart from the components, it’s also important to consider the size of your grow tent/room. Most gardeners prefer using smaller carbon filters, such as 4-inch models, for the small grow tents and the bigger ones (like 6-inch and 8-inch filters) for large rooms. Though, it’s good to know that larger sizes don’t fit some spaces which are extremely tight or compact.
Just as with any other device or machine component, you’d want to rest assured that it’s truly made from high-quality and durable materials that ensure a long lifespan. When it comes to charcoal filters in particular, you should make sure that only the highly durable materials are used for its flange, top, and base.
Thickness & Capacity
With regard to the thickness, remember that the thicker filter implies more carbon. Therefore, the filters that contain a thick carbon layer typically have the greater capacity and hence perform more effectively.
It’s important to take note of the amount of absorbent inside your filter. A good odor control filter usually weighs more, since the amount of so-called activated charcoal (absorbent) within the filter has a direct influence on the absorption capacity.
Generally speaking, you need to choose the thickest carbon filter your particular grow op allows. That’ll give the filter more opportunity to get the odors absorbed altogether. However, keep in mind that the price goes up as the thickness rises.
Quality & Materials
Whether you’re searching for a filter that is galvanized with steel, aluminum, or zinc, be sure that the product can serve you for long period of time. Your best choice is to pick a filter that is made from aluminum. Such a filter is rust-resistant and very lightweight. Not only that it will last longer but also perform better likewise.
All the products listed above are made from top-rated Australian virgin carbon and include aluminum components so that you can’t go wrong with any of them.
It’s recommended to use the compact carbon filters that don’t have in-between air pockets. That’s because such filters produce fewer vibrations and noise. Furthermore, a carbon filter with compact design is capable of filtering odor and smell deeply into the tiny carbon granules. That also means a better air filtration.
At last, you should take into account the cubic feet per minute (cu ft/min aka CFM) of your inline fan. It actually presents the air volume a fan sucks out per minute. You can easily find CFM – it’s either placed in the product description or somewhere on the fan.
Ideally, the CFM rating of the carbon filter should be higher than the CFM of your fan by 20-30%.
Our Final Review for the Best Odor Control for Cannabis
Before setting up a charcoal filter, consider the components of your grow op to make sure that the chosen filter perfectly fits your setup. It must be large enough in order to handle the odor of plants. Plus, it should be compact, thick, and durable. You want a product that effectively works in filtering the harmful contaminants.
Once you’ve taken all these factors into account, it’s much easier to select a product that suits your grow room and meets your own gardening needs. Together with the reviews and top picks showcased above, the best carbon filters are only one click away. Just go ahead!
The team at LEDGrowLightsHQ.com is composed of expert cannabis writers and enthusiasts, many who frequent small grow operations for recreational purposes. We often provide insight from our partners or large publications or magazines.