Air Filters for Cannabis Grow Tents

Last updated: November 28th, 2021

How to get rid of the Smell and stay discreet

Cannabis has a strong scent / smell / aroma.

We growers love it ……. but our neighbours may get offended.

This is perhaps the #1 way for other people to find out about your new hobby.

People can smell it.

Thats why we use Carbon Air Filters.

carbon air filter inside grow tent

Carbon air filters have activated charcoal in them.

Our used, stinky air flows though the carbon.

the carbon pulls out the stinky particles and the air is less smelly.

This method can filter up to about 95% of smell.

Inside a carbon Filter

Some people even say their smell is totally gone.

This is a biological process.

To make this work well … you need to do it a certain way:

1. Move air slowly through them

The more time the carbon has to work, the better it will work.

That’s why you need fan speed control (as described on the previous page).

2. Use a good quality carbon filter

Don’t get the cheapest one becasue those don’t work.

If you like technical stuff, here is why. (skip this section if you like)

The better ones have pressed carbon in them.

Pressed activated carbon pellets from an air filter
↑Pressed activated carbon pellets from a good air filter.
crushed charcoal used from a cheaper model carbon filter

The cheaper ones have just crushed charcoal.

3. Buy a big enough filter

They come in different lengths and diameters.

Carbon Air Filter in 4 inch and 6 inch
Carbon Air Filter in 6 inch and 4 inch

The bigger they are, the more they can filter.

The right size for your setup depends on your tent size.

Which Carbon Air Filter Size do I need?

Tent SizeCarbon Air Filter Size
up to 3ft x 3ft / 1 meter x 1 meter4 – Inch (Amazon)
4ft x 4ft / 1.20 meter x 1.20 meter6 – Inch (Amazon)
6ft x 6ft8 – Inch (Amazon)
8ft x 8ft10 – inch (Amazon)

How to install the Carbon Air Filter?

It gets attached in front of the fan.

So the air is getting pulled though it.

carbon air filter inside tent

Then there is a sock called over it which acts as a prefilter. It keeps dust from clogging up your filter.

You can also use the filter the other way around … by blowing the air into it.

But then you don’t have a pre-filter … and you need to build something.

How to use 2 Carbon Air Filters

You could use 2 carbon filters if your fan is strong enough.

Most fans can do this because Air is very … airy … meaning its easy to move around.

How long does a Carbon Air Filter last?

It depends. But after about 1 year you will start noticing more smell.

A good filter can last 2 years

Then it’s time to change it.