DIY Grow Tent Carbon Filter: Is It Really Worth It?

So you’ve read the articles and followed all the advice, but now you’re wondering if a DIY carbon filter is really worth doing. And if not, what else can you do? It seems like every article or video will tell you to get one of these carbon filters so that you don’t have to worry about your grow tent’s smell anymore.

A DIY grow tent carbon filter could be a really cost-effective and eco-friendly solution to minimize the smell coming from your grow tent. However, its efficiency in removing odors is doubted when compared to readymade grow tent carbon filters.

I see often many articles and videos talking about how to do a DIY grow tent carbon filter, but no one has ever compared purchasing a ready-made carbon filter and doing a homemade alternative. In this article, I will share with you the actual cost breakdown of doing a DIY grow tent carbon filter. Moreover, I am going to show you whether is it really worth making a DIY grow tent carbon filter.

Why Do You Need A Carbon Filter For A Grow Tent?

Grow tents are becoming increasingly popular as a way to grow plants indoors, thanks to the level of control they provide over temperature, light, and air quality.

One of the most important pieces of equipment for any grow tent setup is a carbon filter, which helps to reduce odors and control emissions from the grow tent. Activated carbon filters are widely used for this purpose, as they are effective at trapping odor particles and other airborne contaminants.

The plants raised in a grow tent tend to produce a lot of odors, especially due to the closed environment that the grow tent tends to provide.

These odors could easily accumulate and leak outside the grow tent. If you are placing your grow tent inside your home, you must not risk spreading the stinky smell that a grow tent could produce throughout your entire house.

Getting an odor leak from inside the grow tent into the house is the nightmare of almost every grower. Lucky for you, I wrote a detailed article on how much is it going to cost to actually smell proof a grow tent.

How Does A Carbon Filter Work?

Carbon filters use the principle of adsorption – the adhesion of molecules to a surface – to scrub the odor-rich air found in grow tents. In order to deeply understand how a carbon filter work, you need to follow the air pathway from the moment it gets sucked into the filter from one side until it exits the grow tent from the other side.

Phase 1:Negative Pressure By Exhaust Fan

A carbon filter is connected to the grow tent exhaust fan from the inside so that air passes through the filter first before leaving the tent. Air gets sucked in through the negative pressure that the connected exhaust fan tends to provide.

If you are having doubts about whether to place your carbon filter inside or outside, check this article that I wrote to make up your mind.

Phase 2: Pre-filter Trap Impurities

The filters are usually cylindrical in shape, as this provides the most surface area for the filter to work effectively. The cylinder is hollow from the center.

The filter housing is lined with a pre-filter that can be manufactured from various materials.

Air pass from the grow tent environment through the housing holes into the pre-filter. This process helps in trapping dust particles and other air impurities to prevent them from reaching the carbon bed.

Phase 3: Activated Carbon Bed

Once the air enters the activated carbon stage, odors which are formed of hydrocarbons, attach to carbon particles by adsorption.

Because activated carbon has a large surface area, it can trap odor particles and other airborne contaminants. The quality and surface of the carbon will hugely influence the overall ability of the carbon filter to remove odors.

Phase 4: Air Exiting The Grow Tent

After air gets removed from all the odors that were produced inside the grow tent, it enters the hollow space at the center of the cylindrical shaped filter and exits through the exhaust fan to the outside.

Components Of A Carbon Filter

You already have some idea about the carbon filter’s components from the previous section. However, we will need to dig a little deeper to have a better understanding.

In order to build a fully functioning DIY carbon filter for a grow tent, you will need to get an idea on what are the building blocks of the readymade carbon filter and the materials used. This will allow us to produce a homemade final product just like the manufactured one.

Activated Carbon Bed

Activated carbon, also known as activated charcoal, is a form of carbon that has been treated to create millions of tiny pores between its molecules.

This treatment, called activation, increases the surface area of the carbon and increases its affinity towards odors, that are made from organic hydrocarbons. Activated carbon is used in a variety of applications, from water filtration to air purification. It is also used for medical purposes, such as for treating overdoses and removing poisons from the body due to its excellent absorption abilities.

High-quality carbon particles are critical for any carbon filter to fully block odors from spreading. The best quality carbon particles are those made with Australian virgin charcoal.

Carbon Particles have two gradings:

Carbon Particles TypeAdsorption Capabilities
+1200 IAV Carbon Particles Superior Adsorption Properties
1050 IAV Carbon ParticlesHigh Adsorption Properties


Pre-filters are an important part of the air filtration process and are commonly used inside carbon filters.

Pre-filters are designed to capture larger particles such as dust, pollen, and other impurities. They are usually the first step in the filtration process. By trapping these larger particles, they help to prevent the main carbon filter from becoming clogged and reduce the amount of maintenance required.

A Prefilter might be manufactured with various materials:

  • HEPA
  • Carbon Prefilter Material
  • Cloth

Carbon Filter Housing

The filter housing is the base that holds all of the carbon filter components together. It is important that the housing is filled with holes from all sides to allow air to pass from the grow tent’s environment into the carbon filter.

As I have mentioned before, the carbon filter housing is cylindrical in shape with a hollow center. Usually, the hollow center will have the same diameter as that of the exhaust fan.

The carbon filter housing material is made mainly of:

  • Metal
  • Plastic

DIY Carbon Filter Materials List

Making a DIY carbon filter for a grow tent is a relatively simple and inexpensive process. All you need are a few basic materials and some basic tools.

The materials needed for a DIY carbon filter include:

Activated Charcoal
Carbon Prefilter Material
Plastic Jug Container 6″
Plastic Jug Container 8″
Heavy Duty Duct Tape
PVC Duct 6″
Drill Or Electric screwdriver
3/32 Drill Bolt
PVC Glue
DIY Carbon Filter Materials List

Activated Charcoal

The activated charcoal is the key indicator of whether a carbon filter will eliminate smells properly or not. So, you need to ensure that the carbon particles inside your carbon filter are of high quality. As I have mentioned at the beginning of this article, Australian Virgin Charcoal is the highest quality charcoal on the market today.

You can buy a jar of activated charcoal online or you can find it at any local hardware shop.

Carbon Prefilter Material

A prefilter is essential in eliminating dust and other impurities in the air before reaching the activated carbon bed stage. As a result, the prefilter must be made with pores that are small enough to trap particles but allow the passage of air.

You can find the carbon prefilter material in the form of a roll that you can cut according to your needs. You can check it online here.

Plastic Bucket

The bucket will act as the housing for the carbon filter.

You will need one back and another small one that can fit inside the larger one. The small bucket n. We will assume that your exhaust fan is 6″ in diameter.

You will need:

  • Plastic Bucket 5 gallons
  • Plastic Bucket 3 gallons

You can find it online through this link.

PVC Duct

The PVC duct will be used to connect the plastic bucket straight to the exhaust fan. The PVC duct should be equal in diameter to the small bucket and the exhaust fan. You can find it easily online in any hardware store.

PVC Glue

To cement the small bucket, the PVC glue will be required to glue the center of the large bucket’s base.

Drill With 3/32 Bolt

A drill is needed to make holes inside the two buckets in order to allow the passage of air. The holes must be equally distributed along the sides of the two buckets

You can find the Bosche drill bolt here.

Do not drill holes in the base of any of the two buckets as these bases will be glued together.

If you don’t own a power drill, you could use an electric screwdriver to finish the job.

8 Steps To Make A DIY Carbon Filter For Grow Tents

After knowing about the exact components of a fully functional carbon filter, now its time to roll up your sleeves and implement the 8 steps to make a DIY carbon filter for your grow tent.

Step 1: Prepare All The Items On The Materials List

Failing to plan is planning to fail. You need to get all of the planned items that we are planning to use on the material list mentioned above. You can find all of the items in any local hardware store.

If you are on a limited-time schedule and you don’t have a couple of hours to spare, don’t worry, you can also order all of the items on the list online.

Step 2: Drill Holes On Both Plastic Buckets

Use the power drill or an electric screwdriver to drill holes in both plastic buckets. These holes will allow air passage into and outside of the filter.

A bolt the size of 3/32 would be large enough to allow a good passage of air but not large enough to actually allow carbon particles to escape.

You should aim for around 20 holes for the small 3-gallon bucket and 30 holes for the large 5-gallon bucket.

Step 3: Cut The Prefilter For Both Buckets

Measure the amount of prefilter carbon material needed for both buckets by using a measuring tape.

Use scissors to cut the carbon prefilter roll. The pre-filter should cover both the smaller 3 gallons bucket and the large 5 gallons bucket.

Step 4: Glue Both buckets Together

The small 6″ plastic jug should fit into the large 8″ jug. Apply glue at the center of the 8″ jug base. Make sure that the 6″ jug is centralized inside the 8″ jug to ensure that the activated carbon particles are equally distributed among the carbon bed.

Step 5: Fill In The Activated Carbon Bed

Evenly distribute the activated carbon particles into the carbon bed. The carbon bed should be lined by prefilters from both the outside layer and the inside layer.

If you implemented step 4 correctly, the carbon particles will be evenly distributed.

Step 6: Close The Large Jug Top Lid

Drill a hole in the center of the large bucket’s top lid. The hole should have a diameter equal to the small bucket diameter. This step will provide the appropriate seal to the activated carbon bed.

The drilled hole will be the attachment of the PVC duct that will connect the filter to the exhaust fan.

Step 7: Connect The Carbon Filter To PVC Duct

Attach a 6″ PVC duct to the drilled hole on the large jug top lid. Secure a proper seal using a heavy-duty duct tape.

Connect the other end of the PVC duct to the exhaust fan and wrap it with another strip of duct tape.

Step 8: Run A Smoke Test

This is the final step that we are going to implement in order to make sure that all of the previous steps were done correctly.

Nothing is better than a smoke test to make sure everything is functioning correctly in a carbon filter. Simply burn a small piece of paper and place it beside the carbon filter when the fan is up and running.

To know if your carbon filter is properly sealed with no leakage from any area. Make sure the smoke is being sucked into the carbon filter. This will let you know that there is sufficient negative pressure being produced by the exhaust fan when connected to the carbon filter.

Moreover, run a smell test on the side of the exhaust fan that is outside the grow tent. If the smell is being eliminated, then the activated carbon bed is working properly.

DIY Carbon Filter Cost Breakdown

Activated Charcoal Particles$20
Activated Carbon Prefilter Roll$23
Container Bucket 5 gallons$22
Container Bucket 3 gallons$14
PVC Duct$16
Other Items( PVC Glue, Heavy Duty Duct Tape, Drill Bolt)$25.5
Total DIY Carbon Filter Cost$120.5
DIY Carbon Filter Cost Breakdown

Cheap Carbon Filter For A Grow Tent

A cheap carbon filter version for a grow tent could be done by making a DIY project with materials already available at home to minimize the total cost.

Making a DIY carbon filter is a great achievement. But doing it cheaply is on a whole new level. We will follow on with the same outline of the DIY carbon filter but with a few adjustments.

Old Container Buckets

Instead of purchasing new buckets, you can use some old buckets in your house. However, you have to make sure that there is a large bucket and another small one that fits inside the larger one.

Homemade Prefilter

Instead of using activated carbon prefilter, you can use high-knee cotton socks.

There are different sizes available. However, the bigger the socks size, the easier we can place them around the plastic bucket.

Homemade Activated Charcoal

In order to reduce costs, we will use some of the bbq charcoal pellets you have at home. I know it might sound weird. But these charcoal pellets could provide moderate odor adsorption properties. 

Of course homemade activated charcoal will not last as long as the carbon particles inside readymade filters. But, it will get the job done. You can check the article I wrote on how long grow tent’s carbon filters last.

All you need is to set the right activation process.

Step 1: Grind the Charcoal Particles

Grind the charcoal to reach the small granular size. A small granular size is essential to increase the surface area for higher adsorption efficiency.

Step 2: Let It Sit In an Acid Solution For 24 Hours

The acid solution should be made from homemade fresh lemon juice. The solution should be in a ratio of 1 oz of lemon juice to 3 oz of distilled water.

Step 3: Let It Dry

Leave the charcoal granules to dry in the sun for 48 hours.

Step 4: Heat Activation

Place the charcoal granules inside the oven at 500°F for 15 minutes for the activation process to continue.

DIY Carbon Filter VS Readymade Filters

When comparing between a DIY carbon filter and readymade filter, readymade filters will be clearly superior to its alternative DIY.

We will use the following aspects to compare between both filters:

  • Efficiency
  • Cost
  • Effort And Time

DIY Carbon Filter Effeciency

Clealry, a readymade filter will have much superior efficiency when compared to its DIY alternative. You cannot compare a product that has been mass produced by experts through high technology machines to a carbon filter that has been made at home.

When working on a DIY project, there are a whole lot of steps that can go wrong.

The carbon particles might not be distributed evenly throughout the bed. Moreover, the prefilter might not be tight enough to catch particles and dust from entering the carbon bed leading to an early clogging. I wrote a detailed article on carbon filters getting clogged and how to solve it, you should definitely check it out.

On the other hand, readymade filters will always have standard specs that are constantly being tested for quality assurance. Thus, efficiency is a guaranteed aspect for readymade filters.

DIY Carbon Filter Cost

It have been proven by the cost breakdown that is mentioned in this article that a DIY carbon filter is not cost efficient when compared to readymade carbon filters. A DIY carbon filter will cost an average of $120, while a readymade carbon filter will cost as low as $60. DIY carbon filters will cost almost double the cost of that for a readymade filter.

Effort And Time

Unless you are one of those DIY enthusiasts, you should not be wasting your time on a DIY carbon filter when you can get a readymade filter in just 24 hours with almost half the cost.

The amount of time and mental energy used could be implementing on something that is more critical and productive.


All you need to make a DIY grow tent carbon filter is a carbon filter housing, some activated carbon, and other simple items available at home.

The cost of a DIY grow tent carbon filter is almost double of that of readymade product. Also the readymade carbon filter does have a much higher efficiency in removing odors. Making a DIY carbon filter could be time consuming.

At the end, we have clearly reached to the conclusion that DIY carbon filters for a grow tent is not worth it.

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