Prevent Your Garden from Stinking with The Best Carbon Filter for Your Grow Room

Some of the links in this post are affiliate links. All opinions remain my own.

You may have heard of carbon filters when research the best grow tent set ups.

Maybe you saw the phrase while shopping, or mentioned in reviews or recommendations.

With the amount of information crammed into the descriptions of these, however, it can be overwhelming to understand what they are, why they’re important and what to look for.

This short guide hopes to alleviate some of the confusion and help a first-time grower find the right filter for them.


Quick Top 5 Carbon Filters:

Why is a Carbon Filter Needed?

A grow tent is a great way to create a controlled environment for your plants to thrive in.

However, the enclosed space will produce a lot of heat, humidity, and strong scent.

Often growers underestimate the strength of the smell their plants can put off, and end up buying a filter in a panic.

Going into a filter purchase uninformed, however, can result in lower lifespans for your fans and filter, and a higher likelihood that the filter won’t work at all.

Carbon filters are the preferred choice for most grow tent users.

They’re used across many industries for air purification, and provide effective scent removal at an affordable price.

Because they’re so effective, there’s a large range of filters to choose from, which can often be overwhelming for a first-time buyer.

Doing a bit of reading and research beforehand can save you time, money, and future headaches.

How Does Your Grow Tent’s Setup Affect What You Need?

A more expensive filter will usually weigh more; while this means an increased lifespan for the filter, it’s important to consider your grow tent’s location.

As exhaust fans are usually near the top of your grow tent, make sure that either your tent will be able to support the carbon filter you choose, or you have a way to install a hanging carbon filter.

Some professionals, such as those from General Hydrophonics, go so far as to recommend setting up your carbon filter before you install anything else, including grow lights and settling in your plants.

Don't forget to check out our guide on the best LED grow lights.

Be sure to know your exhaust fan’s CFM (cubic feet per minute) rate as well, since you want your filter to have a higher rating.

You need a filter that has a 20%-30% higher rate to ensure good exhaust at any given time.

A fan with a high CFM rate paired with a carbon filter with a low CFM rate can seriously damage or even burn your fan.

Even with these considerations, however, there tends to be a wide variety of sizes and shapes available to suit your needs and best fit your grow tent.

Just be sure to avoid using an in-line exhaust fan like the kind you’d find in your bathroom.

These fans usually aren’t powerful enough to work with a carbon filter, which means it will have a short lifespan.

How to Find the Best Carbon Filter

Be sure to plan ahead and come prepared when shopping for a carbon filter.

Too often, new growers underestimate the need for a filter, and then rush for the easiest-to-find and cheapest filter.

You’ve already learned about the importance of buying a carbon filter whose CFM is higher than your exhaust fan’s.

It’s also important to consider the quality of the charcoal you’ll be getting in your filter.

Budget out how much you’re willing to spend on a filter:

The higher the cost, the better filter you’ll probably get.

A better filter will also weigh more, as the amount of activated carbon in the filter directly impacts how much odor it will absorb and how long it will work.

Generally, you want to go with the largest filter your grow tent will allow.

This will give the carbon more opportunity to absorb odors from the air.

So long as you choose the right filter to fit your grow tent, you can expect a carbon filter to last at least a year.

And potentially more, depending on the quality and amount of activated carbon in your filter, and the volume of air that moves through it.

Basics for Installing a Carbon Filter

It’s important to consider the way air is flowing when installing a carbon filter.

If installing a carbon filter inside the grow tent, the exhaust fan is pulling air through the filter rather than pushing air through it, which means the filter needs to be in front of the intake of the exhaust fan.

Black Dog LED, suggests that some growers have great success putting their carbon filter outside of their exhaust fan, however.

No matter where you put it, the carbon filter should have a pre-filter in front of it to keep mold, dust and any other particles out of the carbon filter.

It’s also possible to route your grow tent’s exhaust back into your grow tent, instead of letting it vent outside.

If you want to do this, you can connect your exhaust and intake fans, and install your carbon filter on the intake fan instead, either inside or outside.

By doing this, your carbon filter will be able to continuously clean your grow tent's air.

Before installing for the first time, be sure to vacuum your new filter to remove carbon particles.

While it can be a lot to consider, ensuring your carbon filter is installed correctly will help maximize the life of your carbon filter and your fans, as well as maximizing its odor filtration capabilities.

The Best Carbon Filter for a Grow Tent

iPower 4 Inch 190 CFM Duct Inline Fan with 4" Carbon Filter

iPower 4 Inch 190 CFM Duct Inline Fan with 4' Carbon Filter 8 Feet...

The iPower 4 Inch 190 CFM with 4” carbon filter is a lightweight combination of both fan and filter.

The fan itself is made to be low-vibration and quiet, and the included 8 feet of ducting means you have many options for installation.

Included in the kit is everything you need to install the filter either inside or outside your grow-tent, suspended or resting on the floor with the connecting duct.

Plus, the filter comes with a two-year life expectancy, and includes a pre-filter which only needs to be changed every six months.

The filter has a 1050+ IAV (Iodine Adsorption Value).

People seem to love the filter and fan, citing few to no problems.

One of the only issues is an occasional problem with the fan itself, and how loud it can be when not on its maximum speed.

Amagabeli 4"

iPower 4 Inch 190 CFM Duct Inline Fan with 4' Carbon Filter 8 Feet...

The Amagabeli 4 Inch carbon filter is an activated charcoal filter that has a 1050+ IAV rating and weighs about 7.5 pounds.

Made to fit any 4 inch duct or fan, it boasts 190 CFM, and comes with a washable pre-filter.

The Amagabeli is designed to be reversible, as well, which means it can be easily adjusted to fit either an intake or an outtake fan.

Some people do think that the flange is a bit too small.

Most, however, are able to adjust to the size difference easily.

For a simple and straightforward activated charcoal air filter, the Amagabeli has set itself up as an easy to maintain, solidly built and reliable choice.

Growsun Air 

Growsun 6 Inch 400 CFM Inline Carbon Filter Fan Combo for Grow Tent,...

The Growsun Air Carbon Filter is a 4 inch by 10 inch filter.

It includes a prefilter, but little information can be found on its CFM.

At 5.5 pounds, this filter is a comparably lightweight option.

It does its job well, and any issues encountered will be met by a great customer service team, a must for a first-time user.

The Vivosun 4 inch air carbon filter is a 1050+ IAV rated, reversible air filter with an included velcro prefilter.

Weighing in at 7.3 pounds, this filter boasts a two year maximum lifespan; the manufacturer recommends reversing the filter to help increase the lifespan, and replacing it after one year for maximum effectiveness.

The flanges on the filter are able to be swapped easily to allow for it to be installed as either an intake filter or an exhaust filter.

People keep coming back to the Vivosun because it's reliable, works and is backed by a great customer service team.

iPower 6" Filter

iPower GLFILT6M 6 Inch Air Carbon Filter Odor Control Scrubber with...

The iPower 6 inch air power filter is 16 inches in length.

It comes with a washable prefilter and a reversible flange for installation as either an intake or an exhaust filter, as well as helping increase the lifespan to two years.

Made with 1050+ IAV charcoal and weighing in at 11 pounds, this filter makes up for its larger size with increased effectiveness.

The flange is a little smaller than you'd think.

However, this does not seem to have much of an impact on most growers.


If you don't want your neighbors finding out about your marijuana grow op, then you NEED to invest in a carbon filter.

This is one piece of equipment you don't want to skimp on either.

You can get the top of the line, for a fair price.

Just make sure to get a carbon filter that will fit your setup and large enough to handle the smell of your plants.

Do you use a carbon filter with your grows?

We'd love to hear any tips you have on them in the comments below.

Last update on 2019-08-19 / Affiliate links / Images from Amazon Product Advertising API

Tony Hand Jr

Tony Jr is the Founder and Editor-in-Chief of If he’s not smoking, writing or watching anime, then you can usually find him on the couch yelling over terrible play calling. You can read more about him here

Click Here to Leave a Comment Below 0 comments