How Long Do Carbon Filters Last in a Grow Tent?

Growers could be sometime confused about how long carbon filters last in a grow tent and how often we change them. After all, the last thing any grower would want is smell leaking out of the grow tent, and eventually, out of the house.

Manufacturers state that 1-2 years is the average lifespan of any carbon filter operating in a grow tent continuously 24/7. According to several critical factors that impact the lifespan of a carbon filter in a grow tent, the lifespan could be extended by additional 2 years.

I found it irritating that there are some critical old-school tricks that many newbie growers are not aware of.

Manufacturers tend to give grow tent carbon filters a set lifespan period. However, there are a lot of variables that control such lifespan periods. Moreover, certain tips could be used that I found almost nobody talking about that will potentially boost the efficiency of any grow tent carbon filter and extend its lifespan.

This post will be a sequential step-by-step guide to know everything about when your grow tent carbon filter needs replacement and how to use some tips and tricks to get around replacing it.

Factors Affecting How Long A Grow Tent Carbon Filter Last

Before diving into the critical information, you need to get a brief summary on what are the variables that affect a to grow tent carbon filter.

1-Quality Of Activated Carbon

Activated carbon filters are designed to remove harmful toxins and chemicals from the air, and they play an important role in how long a grow tent carbon filter would last.

Poor-quality activated carbon will not adsorb as many odors as high-quality activated carbon, and it will also lose its efficiency more quickly.

It is important to select a high-quality activated carbon filter for your grow tent carbon filtration system. This will ensure that the grow tent carbon filter is working as it should, and that it is able to remove any produced odor and prevent it from leaking outside of the grow tent.

When it comes to choosing an activated carbon filter with high adsorption properties, there is really nothing better than Australian-certified virgin carbon.

IAV RatingAdsorption Properties
Australian 1050m2/gm IAVHigh Adsorption Properties
Australian 1200m2/gm IAVSuper-High Adsorption Properties
Australian Grade Activated Carbon

The difference between 1050 IAV and +1200 IAV is the amount of surface area a gram of carbon have. the +1200 IAV Australian carbon have more porous microstructure than that the 1050 IAV, which allow it to adsorp higher amounts of odors per gram. We will dig deeper into the importance of surface area of carbon in the next section.

2-Carbon Filter Particle Size

Basically, there are two main types of carbon particles in any carbon filter: they are Granular carbon particle and Pellete carbon particles.

Granular Carbon Particles: As the name suggests, the carbon particles in this type is crushed down to granular sizes, which have a very high surface area per one gram of carbon. thus, it have the higher efficiency to adsorp odor.

Pellete Carbon Particles: This carbon particles are much larger in size, and it’s smaller surface area cannot be compared to granular carbon particles by any means.

To give you an idea of why surface area and particle size matter to a grow tent carbon filter, take a look on the example below.

A 50 grams of activated carbon that have sufficient porous surface would match the surface area of 10 football fields. Can you even imagine how large 50 grams of carbon could be and their effect on your grow tent odor control.

3-Types of Plants Grown

The types of plants you are growing does significantly impact the grow tent carbon filter logenvity. You cannot grow lettuce in one cycle and herbs in another cycle and expect them to have the same effect on your carbon filter.

Highly aromatic plants that produce larger amount of odors will quickly fill up the porous microstructure of any carbon filter particles.


Grow tent get high humidity levels all the time. It happens as a result of the continouse presence of water and heat in the same place.

The definition of humidity is the quantity representing the amount of water vapour in the atmosphere. This means that the higher the humidity inside the grow tent, the higher the amount of water vapour the will be present in the air.

Water vapour tend to enter and occupy large amounts of pores in the carbon microstructure competing with other compounds like odors. As a result, the grow tent carbon filter efficiency will significantly decrease, and smell might start to get outside.

Controlling the grow tent’s humidity is crucial to keep a carbon filter efficient. You should set your dehumidifier to a maximum limit of 80% .

5-Carbon Filter Type

This is a popular trick that everybody does. However, I am going to share it with you just in case you didn’t know about it.

Carbon filters comes in two forms : Reversible and Irreversable.

The reversible carbon filter has two operating ends that you can use. After a while of using it, you can simply reverse the ends and use the other side of the filter to get a longer lifespan.

You are probably asking how exactly is flipping carbon filter ends would extend it’s lifespan? when the carbon filter is in operation, the end that is directed towards the inside of the grow tent gets exposed to higher levels of compounds in the air when compared to the other end of the filter that is present outside. Chemical compounds might be water vapour odors, and other stuff.

By reversing the carbon filter ends, you are simply taking advantage of the other side being less exposed to other elements and thus, still have several months of lifespan left available.

How To Know That A Grow Tent Carbon Filter Needs Replacement?

This might seem like an overwhelming question that every grower tend to overthink about. However, the answer to it is quite simple. The answer is as simple as “use your nose”. You read it right, using your nose is the most accurate test you could run to know the right time to change your carbon filter in the grow tent.

Step 1: Take A One Day Break Away From Your Grow Tent

Step 2: Before Smelling The Grow Tent, Do Any Excercise To Boost Your Bloow Flow

Step 3: Smell The Grow Tent Carfully For Any Smell Leakage

If you went straight to your grow tent and run what I am calling a “Nose Test” on it. In most cases, you wouldn’t smell anything unless you follow the next guidelines.

Being around your grow tent daily will most probably result in you having sensory adaptation.

Adaptation To Grow Tent Smell

Sensory adaptation means simply that your nose get adapted to certain smells if it has been around it long enough. Some studies have shown that all it takes is two breaths for a nose to adapt to a certain scent, after that, it switch off making you no longer able to smell it again.

Did you ever wonder why does your house smell so much different when you return from a 1 week vacation outside of town? Sensory adaptation is the answer.

You need to take a long day outside of your home inorder to give your sensory nerves a break before returning back and smelling anything.

To enhance your smelling abilities for a temporary short period of time try increasing your overall blood flow. This small trick that is used by perfumers in the fragrances industry before testing out new scents.

Increasing your overall blood flow by doing any type of simple cardio exercise will increase the blood flowing to the olfactory nerves, giving you a temporary boost in your smelling abilities.

How To Clean A Carbon Filter Grow tent?

Following a regular cleaning schedule is critical in keeping the carbon filter efficient. A grow tent is the perfect place for accumulation of dust and other particles. You should do clean your carbon filter regularly every 3 months.

Step 1: get the carbon filter outside the grow tent carefully to avoid any dust falling on your plants.

Step 2: Use a toothbrush to clean the filter outer surface from any accumulated particles.

Step 3: Run an air blower into the carbon particles to remove the trapped dust inside.

Step 4: Run a smell test following the guideline mentioned in the previous section.

Step 5: If the grow tent is still smelly, you must reactivate the activated carbon again.

In case that regular cleaning didn’t boost the carbon filter efficiency the way you were expecting. Then its time to try reactivating your carbon filter.

How To Make A Carbon Filter Last Longer?

As time passes, carbon efficiency degrades, Reactivating a carbon filter will instantly boost it’s efficiency. As a result, the carbon filter will last longer periods of time.

Its funny that I found no one talking about this old school trick and how significant its effect can be on any carbon filter. You can follow on to the next steps if you want to extend some extra months, or even years out of your grow tent carbon filter.

However, if you don’t have the time to implement these steps, you can go ahead and purchase a new carbon filter instead.

Step 1: Water Rinse Carbon Particles

Unpack the carbon particles from the filter and put it inside a bowel. Rinse the carbon particles with water till there is no yellow or white colour is present.

Step 2: Let The Carbon Particles Dry

Place the carbon particles on a metal tray. Place the metal tray in a sunny area till they completely dry out.

Step 3: Heat The Carbon Particles

You should heat the carbon particles for 10 minutes in a minimum of 930°F. In this step you can use a home oven or a bbq grill. However, make sure to keep direct fire away from the carbon particles to avoid it turning into ashes.

Step 4: Let Carbon Particles Cool, Then Topp it Up

Carbon will take a while before it finally cool down so make sure to leave sufficient time for it. After the heating process carbon will lose around 10% of it’s total final mass, you should topp it up with new activated charcoal to make up for the mass loss.


All of the mentioned information in this article will have a bearing on how long your carbon filters will last. However, choosing the right type of carbon and being careful to maintain your grow tent humidity-level is also important.

Your carbon filters should be able to remove any produced odors from the grow tent, and it should also endure for an average of 1-2 years. You can run a smell test on the grow tent to know if the carbon filter is blocking odors efficiently or not.

If you would like to try and boost the grow tent carbon filter instantly, you should reactivated the charcoal again using the guidelines I have mentioned above


Activated Carbon

Sensory Adaptation

Leave a Reply

Your email address will not be published. Required fields are marked *

Recent Posts