Top 6 Best Carbon Filter for Grow Room – Reviews and Advice

Indoor gardening has grown so popular these days. Perhaps due to the fact that when you grow plants in a grow room, it is easy to monitor the progress of the plants and this will translate to increased yields. However, there is a problem, how do you deal with the sharp pungent smell coming from the grow room spreading to the living room? For instance, if you are growing weed does it mean that all your nosy neighbors have to know about it? As much as we might want to ignore it the smell can at times be annoying and that’s why you are going to need carbon filters. And, all carbon filters are not the same bringing us to the question for the day best carbon filter for grow room?

Why use carbon filters?

Is the use of carbon filters the only way to reduce the spread of the pungent smell that comes from a grow room? The answer is no however, carbon filters are the most effective and highly preferred way to absorb smells that go beyond the grow room. The use of gel and air purifiers only masks the smell.   

There are over 200 carbon filter brands in the market today all which differ when it comes to features and effectiveness. Every brand claims that their product is the best and without proper guidance, you can easily end up purchasing a rather less effective product. In this post, however, we have reviewed 6 of the best carbon filter for grow room. All you have to do is read through the features, pros, and cons and determine what suits you best.

What to look for when purchasing best carbon filters?

Area to be covered

The area to be covered has a huge influence on the carbon filter you should purchase. If the area is big then it means that you are going to need a bigger carbon filter. The opposite is also true.

Material used               

Due to its lightweight and affordability aluminum is highly preferred in making carbon filters. The only problem with this is that aluminum is highly corrosive. The best aluminum carbon filters are coated with a noncorrosive material. Alternatively, steel can be used. Being a heavy metal, steel carbon filters do not corrode easily making them durable. Other materials can still be used and as long as they don’t corrode or leak the smell being absorbed.

The quality of the carbon

Different carbon filters differ when it comes to the quality of the carbon and ability to absorb the smell. Depending on what you are growing at times the scent can be too much and this means that you are going to need some quality carbon. Active carbon has the ability to absorb impurities, pungent smell, and smoke, making it the best option especially if you are growing cannabis and you don’t want your nosy neighbors to know about it.


You don’t want to be replacing the carbon filter every month, do you? The best carbon filter for grow room are durable but we can’t ignore the fact that it is nearly impossible to judge whether a given carbon filter will be durable or not just by looking at it. Well, this should not be the case if you are reading this review since we shall discuss in details on whether a given carbon filter brand is durable or not.


Well, this is not always a necessity but given the variety of designs in the market today, there is no harm with going for a design that your heart desires. In particular, cone-shaped carbon filters have a reputation to maximizing air flow by absorbing air coming from all directions then deliver clean and fresh air.


A versatile carbon filter means that it can be used just anywhere and not only in a grow room.


You can’t say you didn’t see this one coming, can you? Well, you should always consider the price of the carbon filters, after all, you can’t purchase what you can’t afford. In most cases, there are high chances of limiting yourself to price as the only factor. This should not be the case and that’s why in our review we have mixed up things to accommodate various spending capacities not forgetting that, expensive doesn’t always mean the best quality.

How to determine the size of the carbon filter to purchase?

For effectiveness, you should always see to it that you purchase a carbon filter that will match the size of your grow room. To get this right you must calculate the volume of the grow tent which is usually in the shape of a cube or cuboids. From basic 4th grade mathematics, how do you calculate the volume of a cuboid?

Volume = Length × Width × Height

How is the volume useful in determining what carbon filter to buy? Manufactures use CFM as a measure of calculating how effective a given carbon filter is. Divide the volume of the grow area by three and find a carbon filter that has a high CFM than the grow room.

What is a pre-filter?

A pre-filter is fixed in a carbon filter so as to extend its lifespan by removing sediments and impurities from the grow room. The best carbon filters have installed pre-filters.

Some contaminants may pass through the carbon filter but with a pre-filter, the sediment s will be trapped. It is highly recommended that you opt for carbon filters where the pre-filter is in a rather separate canister.

Reviews of the best carbon filter for grow room

As mentioned earlier, depending on what you are growing, the smell from the grow room can be too much such that it not only affects you but your immediate neighbors as well! To avoid this you have to install a carbon filter in the grow room. However, deciding on the best can at times be overwhelming especially if you don’t know what you are looking. The following is a comprehensive review of 6 of the best carbon filter in the market today:

1. iPower 4 Inch Air Carbon Filter

iPower 4 Inch Air Carbon Filter is 4 inches in diameter and 12 inches long and it is no surprise that it is our top pick in our review of the best carbon filters to use in a grow room. To begin with, iPower 4 Inch Air Carbon Filter uses RC Australian Virgin activated carbon that is considered one of the best qualities in the modern world. It is thick to allow maximum absorption and not only helps filter carbon but also helps eliminate toxic chemicals, excessive heat, and bad odor.

It is made of high-quality aluminum for maximum strength. At the base, iPower 4 Inch Air Carbon Filter is reversible in the sense that you can easily reverse the charcoal canister turning the filter upside down to make used of the unused part of the filter.

This particular carbon filter doesn’t allow molds, mildew and other pollutants to build up in the air. It is very cheap and comes with a 2 years warranty from the manufacturer. iPower 4 Inch Air Carbon Filter is versatile and can also be used in bathrooms, kitchens, and greenhouses.

As part of additional accessories iPower 4 Inch, Air Carbon Filter comes with two additional pre-filters made of poly-cotton. The pre-filter helps absorb large contaminants before they can reach the carbon filter.


  • Relatively affordable
  • The CFM inline duct ensures that it runs quickly
  • Comes with 2yrs warranty
  • Versatile
  • High-quality carbon filter


  • The pre-filter has to be replaced every 6 months

2. CoolGrows 4 Inch Air Carbon Filter

If you are looking for a cheap yet top-notch quality carbon filter for your grow room then you should consider purchasing CoolGrows 4 Inch Air Carbon Filter. The filter is packed dense such that it absorbs 99.8% of the air passing through it. Barely any odor or chemical contaminant can escape from the grow room if you use this CoolGrows 4 Inch Air Carbon Filter.

High grade 1050+ Australian virgin bed is used; it not only absorbs bad odors but also chemicals and impurities in the air. CoolGrows 4 Inch Air Carbon Filter is made of galvanized steel which is stronger and more durable than aluminum. Steel doesn’t rust or corrode easily meaning that this particular carbon filter will serve you for years without the need to replace it

There is a 53% open area on the outer mesh so as to help optimize the smooth flow of air in the grow tent.


  • Durable
  • Affordable
  • 1yr warranty from the manufacturer
  • Compatible with a fun
  • Easy installation
  • Versatile


  • It is not reversible

3. Vivosun 4 Inch Air Carbon Filter

Vivosun is such a reputable company when it comes to making high-quality carbon filters and Vivosun 4 Inch Air Carbon Filter is no exemption. The carbon filter is has a diameter of 4 inches and a length of 14 inches. This is one among a few brands that claim to filter nearly 100% of the Air that passes through it.

Vivosun 4 Inch Air Carbon Filter has numerous applications with its main application being in a grow room to eliminate bad odor, a chemical in the air and impurities. It can also be used as an exhaust or intake filter thanks for the best inline fans to help improve the circulation of air in the grow room.

The filter is made from imported Australian Virgin Activated charcoal considered the best absorbent carbon in the world. The base and flange are reversible meaning that you can turn the carbon upside down to make use of the unused part of the filter.

Vivosun 4 Inch Air Carbon Filter has a pre-filter as an additional accessory. The work of the pre-filter is to ensure that only clean air reaches the main filter. The fact that it is made of galvanized steel means that it is durable and with serving you for years without a necessity to replace it!


  • Durable
  • From a reputable brand
  • Budget-friendly


  • Regular maintenance is needed
  • Rather noisy
  • Only suits small grow rooms
  • Pre-filters have a short lifespan

4. Apollo Horticulture 6 Inch Premium Charcoal Air Filter

If you have been doing indoor gardening long enough, then the word Apollo is not a new term to you. The company also makes carbon filters that are quite a darling to many people. Apollo Horticulture 6 Inch Premium Charcoal Air Filter uses Australian raw carbon and is 50mm thick to ensure maximum absorption.

It absorbs all kinds of smells and is made from high-quality lightweight aluminum. This brand is suitable to use in all grow houses irrespective of what you are growing.


  • Easy to install
  • High-quality raw carbon is used
  • Thick carbon layer


  • Not reversible
  • The aluminum corrodes easily over time

5. Activated Charcoal Carbon Filter

Activated Charcoal Carbon Filter is the only brand packed with small granules in this list. What does this mean? It means that this particular carbon filter has 15 more activated carbon than normal brands in the market today.

Only high-grade Western Australia charcoal carbon is used. The thickness of the carbon bed is 46mm. Activated Charcoal Carbon Filter has an inbuilt fun to ensure that it doesn’t only absorb the pungent smell from grow rooms but also purifies the air. This makes it suitable to use in hydroponics, greenhouses and small grow rooms.

Lightweight aluminum is used and the model comes with two washable pre-filters. Given its initial price, this is cheap.


  • Uses only high-quality aluminum
  • Easy installation
  • Affordable
  • Has a pre-filter


  • Not durable
  • Requires regular maintenance

6. Phresh Filter 701005 Filter

Coming up at last in our review of the best carbon filter for grow room is none other than Phresh Filter 701005 Filter. It is 6 Inch diameter and 16 Inch in length and given its features, it would have been unfair to snub this brand a chance to be on this list.

Phresh Filter 701005 Filter uses certified virgin carbon bed that is 46mm thick. This is the brand to go by if you want fresh air not only in the grow room but also in the surrounding vicinities. The model has an anti-air bypass system that helps maximize air flow.


  • Have an anti-air bypass system
  • 1 yr warranty from the manufacturer
  • Durable
  • Has a pre-filter


  • Expensive
  • The base and flange cannot be reversed

How to set carbon filter for a grow room?

Carbon filters are in the shape of a tube and depending on the material used it can be pretty heavy. The goal of installing the filters is to neutralize the smell passing through it. The following is a step by step guide on how you should set up carbon filter for a grow room:

  • Find the right size and model carbon filter for the grow room.
  • Though optional, you are required to connect the carbon filter a fan
  • Hang the carbon filter at the top of the grow room using YOYO hangers
  • Feel free to use duct tape if you feel the hangers are not stable enough


For people practicing indoor gardening, carbon filters are more of a necessity than an option. In this post, we have reviewed 6 of the best carbon filter for grow room and it is my hope that the information was useful to you. Show some love by sharing this post with a friend or two and don’t forget to leave a comment in the comment section below.

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