Ventilation is hugely important for your grow room.
And a hugely important part of your ventilation system is your inline carbon filter.
What does a carbon filter do?
- Keeps harmful pests out
- Keeps unwanted smells and allergens in
This guide has everything you need to know about inline carbon filters, including our top picks and how to choose the right one for you.
Let’s start with the basics.
What Is An Inline Carbon Filter?
Carbon filters are used to neutralize or reduce the odors your plants produce.
Normally, a carbon filter needs to be installed with an inline fan in order to work properly. The fan draws air into the carbon filter, and the air is then purified by activated carbon inside the filter.
If you already have a fan, make sure that you choose a carbon filter that fits. Specifically, you’ll want to focus on the duct width.
You can also buy fan and filter combos that contain everything your odor-eliminating system needs.
Without further ado, our top 8 picks.
8 Best Carbon Filters For Grow Rooms
Here is a roundup of 8 best carbon filters for your grow room.
1. TerraBloom 6-Inch Air Carbon Filter
| Type | Filter only |
| Weight | 18 lbs |
| Dimensions | 6” duct opening × 24.6” long 9.6″ diameter |
| More Info | View on Amazon → |
Whether it’s carbon air filters or inline fans, no company has a better combination of price, performance, and customer service than TerraBloom.
They offer several models of 4, 6, and 8-inch carbon filters with this 6-inch model their overall best. Not only is 6 inches a common size for most grow room setups, but this 24-inch long model works with up to 550 CFM with a 1.8″ layer of top-grade RC-48 activated Australian virgin charcoal.
The carbon bed is 46 mm thick, which is at least 15% thicker than the standard 38 mm carbon beds on economy models found elsewhere online.
That thickness and quality is unparalleled and means the elite odor elimination for up to 2 years.
It’s also covered by TerraBloom’s 90-day warranty.
If you’re looking for a carbon filter compatible with 6-inch ducting, stop here. You won’t be disappointed.
Pros of the TerraBloom 6-Inch Premium Air Carbon Filter
- 46 mm thick carbon bed with top-grade RC-48 activated charcoal
- Amazing customer service from my favorite brand of filters and fans
- Works with up to 550 CFM systems
Cons of the TerraBloom 6-Inch Premium Air Carbon Filter
- A little more expensive than other carbon filters on this list, but that’s the price of quality and customer service
2. VIVOSUN 6-Inch Air Carbon Filter
| Type | Filter only |
| Weight | 11 lbs |
| Dimensions | 6” × 18” |
| More Info | View on Amazon → |
Made of imported Virgin Australian activated charcoal, the VIVOSUN 6-Inch Air Carbon Filter has a 1050+ RC-48 carbon bed with optimal surface area per carbon particle that captures three times more carbon particles than average.
This carbon filter protects you from chemical irritants and eliminates odors from your indoor plants as well as bathrooms, kitchens, basements, and almost anything including your pets and smoking. It has a CFM of up to 450-500.
It comes with detachable and reversible filter flanges for full use. The inner and outer mesh provide a 53% open area for increased airflow. Also included is a carbon filter belt.
There are three variants that you can choose from: 4-inch, 6-inch and 8-inch.
The VIVOSUN 6-Inch Air Carbon Filter is 2 inches longer than other carbon filters of similar size. While most filters are 6” × 16”, this filter measures 6” × 18”. Note this is still shorter than our top-ranked TerraBloom model.
This filter works both as an exhaust filter and as an intake filter. A free velcro pre-filter belt is also included.
VIVOSUN generally has good customer support, and in most cases if you get a faulty filter that has some issue, VIVOSUN gets it replaced for you.
Pros of the VIVOSUN 6-Inch Air Carbon Filter
- Superior carbon quality
- Effective odor control
- Includes a free pre-filter
- Simple and easy setup
- Durable
Cons of the VIVOSUN 6-Inch Air Carbon Filter
- Not very suitable for really heavy odors
- Sometimes this filter increases the temperature of your grow tent
3. iPower 4-Inch Air Carbon Filter
| Type | Filter only |
| Weight | 6 lbs |
| Dimensions | 4” × 12” |
| More Info | View on Amazon → |
The iPower 4-Inch Air Carbon Filter uses 1050+ IAV Australian RC-412 Activated Carbon, which is one of the world’s most absorbent carbons available. The virgin carbons used in this filter come from some of the oldest and most-pressurized carbon sources.
The carbon layer is 50 mm thick for higher absorption and performance. The filter absorbs and eliminates some of the most undesirable odors and harmful chemicals in the air. The carbon filter cap is manufactured with high-quality and durable aluminum, which gives it maximum strength and long-lasting effects.
The aluminum construction makes it 50% lighter than similar carbon filters.
It’s recommended to replace the included pre-filter every 6 months in order to protect the filter.
Increased airflow is made possible due to the inner and outer mesh having a 53% open area.
It has a reversible flange and base for an extended service life, and you can expect a life expectancy of up to 2 years.
This model can be used as an exhaust filter as well as an intake filter.
After a year’s use, you have to remove the top flange and the bottom mount, flip the filter upside down, and remount the flange and the mount so that you can use it for another year.
iPower has inline fans and ducting which you can use this filter with.
Pros of the iPower 4-Inch Air Carbon Filter
- 50 mm thick carbon bed
- Lightweight and inexpensive
Cons of the iPower 4-Inch Air Carbon Filter
- May not be very effective in removing odor completely
- Some filters may not last long
4. AC Infinity 6-Inch Air Carbon Filter
| Type | Filter only |
| Weight | 9 lbs |
| Dimensions | 6” × 16” |
| More Info | View on Amazon → |
Designed to eliminate odors and chemicals for both grow tents and hydroponic grow rooms, the AC Infinity Air Carbon Filter comes with a premium-grade Australian Virgin charcoal bed rated at 1200+ IAV that has higher absorption and a longer lifespan.
The air filter is made with RC-412 pore-sized activated carbon that’s highly absorbable. It has full air pass-through, which enables maximum airflow while diminishing CFM loss by using an aluminum mesh that lines both the inner chamber and the outer body. This filter has an airflow rating of 410 CFM.
The pre-filter cloth that comes with the filter is an easy-to-wash sleeve that prevents carbon residue from building up and keeps the filter clean. It goes over the mesh body and is machine washable.
This carbon filter contains heavy-duty stainless steel flanges, aluminum meshing, and a cloth pre-filter. You can reverse the flanges to extend the lifespan of the filter.
It has a high microporosity and surface area rating, which paves the way for a 60 mm thick charcoal bed and a 55% open mesh area. This combination enables a higher absorption rate without restricting free airflow and allows the carbon filter to last up to 33% longer.
Also suitable for smoking lounges and kitchens, this carbon filter looks sleek and comes in three sizes: 4-inch, 6-inch, and 8-inch.
Pros of the AC Infinity Air Carbon Filter
- Solid airflow up to 410 CFM
- Looks snazzy and beautiful
- Runs quietly
Cons of the AC Infinity Air Carbon Filter
- In some cases, performance drops after about 6 weeks
- Doesn’t come with straps or installation belts
5. G HYDRO 4-Inch Air Carbon Filter
| Type | Filter only |
| Weight | 6.2 lbs |
| Dimensions | 4” × 14” |
| More Info | View on Amazon → |
The specially-designed black G HYDRO 4-Inch Air Carbon Filter has an airflow of up to 210 CFM and a panel ventilation rate of up to 53%, which helps to drastically reduce air volume loss and increase work efficiency.
The carbon filter is made of ultralight ABS material and 1050+ RC-48 Australian Virgin charcoal, one of the most absorbent carbons, and the optimal shape of each particle is scientifically designed to provide 100% airflow.
This filter’s design enables better absorption of odors and air pollutants, including smoke, kitchen fumes, and chemical irritants.
A free pre-filter made out of 150 GSM high-quality material with a new needle knitting process is included, which blocks 99% of the particles and prevents the filter from becoming clogged.
The filter can be used as either an intake filter or an exhaust filter.
Pros of the G HYDRO 4-Inch Air Carbon Filter
- Matte black finish
- Strong and sturdy
Cons of the G HYDRO 4-Inch Air Carbon Filter
- Reverse installation requires a screwdriver
- May sometimes arrive broken and without no straps
6. VIVOSUN 4-Inch 203 CFM Inline Duct Fan
| Type | Fan + filter |
| Weight | 17.3 lbs |
| Dimensions | 4” × 14” |
| More Info | View on Amazon → |
This carbon filter from VIVOSUN comes with a 4-inch 203 CFM, high-flow duct fan that has a fan speed of 2500 RPM, so you don’t need to worry about buying a fan separately or about your carbon filter fitting properly with the fan you have.
The low-noise fan only puts out 49 dB but is powerful and moves air through your target location efficiently for optimal ventilation, working together with the carbon filter to filter out any unpleasant smells your plants may have.
The carbon filter is made out of 1050+ RC-48 Australian Virgin activated charcoal, whose inner and outer mesh provides a 53% open area for increased airflow. The reversible flange and base provide the filter with a longer service life and a life expectancy of up to 2 years.
It works as both an intake filter and exhaust filter. The preferred method of installation is both fan and filter inside the grow tent, but other possible methods are both fan and filter outside the grow tent, or either one of them inside and the other outside.
Two belts are included to allow for easier installation. The system is easy to install and the carbon filter has effective odor control, eliminating some most pungent smells.
The fan plus filter combo comes with a free pre-filter, which is recommended to be changed every six months or after every grow cycle.
This is a 4-inch filter, but you can also buy their 6-inch filter. Like many other filters, this can also be used in bathrooms, kitchens, and other places as well.
Pros of the VIVOSUN 4-Inch Fan+Filter Combo
- Comes with a compatible fan
- Effective odor removal
- Easy to install
Cons of the VIVOSUN 4-Inch Fan+Filter Combo
- In rare cases, you may get defective items that may not last long and need replacement
7. iPower 4-Inch 190 CFM Duct Inline Fan
| Type | Fan + filter |
| Weight | 16.1 lbs |
| Dimensions | 4” × 12” |
| More Info | View on Amazon → |
This iPower fan and filter combo has a 4-Inch 190 CFM Duct Inline Fan and is made of high-quality UL parts with composite fan blades and center hub to reduce vibrations and ensure quiet operation. It has a permanently lubricated bearing that requires no maintenance.
The 4-inch carbon filter is made of 1050+ IAV Australian virgin activated RC-412 charcoal to remove odors and other harmful substances. It has large mesh openings for a highly-effective scrub.
A pre-filter comes included for the carbon filter, which you should change every 6 months.
The system comes with a 4-inch uninsulated aluminum ducting that’s 8 feet long. It has a temperature range of about 0-185°F and comes with 2 stainless metal clamps.
It has a flame-retardant coating and corrosion-resistant wire helix, making it safe and corrosion-free.
This system, which can be used as both an intake filter and an exhaust filter, is also effective in removing the heat from your grow rooms and tents to bring in fresh air. It can be positioned in four different ways with easy installation.
Pros of the iPower 4 Inch Filter+Fan Combo
- Complete combo for odor and heat elimination
- Requires no maintenance
- Includes 8 feet of ducting
Cons of the iPower 4 Inch Filter+Fan Combo
- Doesn’t have a long lifespan
- Fan doesn’t have speed control
- May be a bit noisy
8. VIVOSUN 8-Inch 720 CFM Inline Duct Fan
| Type | Fan + filter |
| Weight | 30.2 lbs |
| Dimensions | 8” × 22” |
| More Info | View on Amazon → |
The VIVOSUN 8-Inch 720 CFM Inline Duct Fan with 8-Inch Carbon Filter comes with a powerful airflow fan that has a speed of 2450 RPM for an airflow of 720 CFM. It puts out only 37 dB of noise.
The fan is engineered for maximum boost and minimal noise and with quiet and efficient operation. It has balanced blades that enable increased air supply and venting of exhaust air. The motor has a permanently lubricated bearing that requires no maintenance. The fan housing is made of durable plastic. It also has a variable speed controller.
The 8” × 22” superior carbon filter consists of a 1050+ RC-48 Australian Virgin charcoal bed and has effective odor control to eliminate pungent smells and other unwanted odors and particles from grow tents.
A pre-filter comes included, which you have to replace every six months.
The 53% open area allows for increased airflow, and the flange and base are reversible, just like in other VIVOSUN filters, giving the carbon filter a lifespan of about 2 years.
Installation is easy and the system comes with two belts to help.
Like the VIVOSUN 4-Inch 204 CFM Inline Fan and Carbon Filter combo, this system can be installed in four different ways and can be used as either an exhaust and an intake filter.
Pros of the VIVOSUN 8-Inch Fan+Filter Combo
- Larger, 8-inch size for bigger systems
- Comes with a fan that has a variable speed controller
- Easy to set up
- Great bang for your buck
Cons of the VIVOSUN 8-Inch Fan+Filter Combo:
- Fan doesn’t last long and may not work properly or stop working
- Not the best model from VIVOSUN
How To Choose The Best Carbon Filter For Your Grow Room
Choosing the best carbon filter for your grow room isn’t hard, but it is important. Here are three things to keep in mind:
- Your carbon filter needs an inline fan that can direct air into the filter for purification, so make sure your fan and filter are compatible.
- Many carbon filter companies have their own fans that you can buy separately. If you don’t buy a combo fan and filter, try to get a fan and filter from the same company. That’s why we love TerraBloom so much. Their fans and filters are both top-of-the-line.
- Carbon filters don’t last forever, so take care of them.
If you have any questions about choosing the best carbon filter for grow room use, comment below!