Odour is a fact of life when growing marijuana, and controlling it can make the difference between protecting your freedom and winding up in a jail cell – because let’s face it, you don’t want nosey neighbours getting suspicious.

If you are growing outdoors, odour should not be too much of a problem – as long as you have picked your growing areas sensibly (i.e. not in the middle of a built up complex). However, when you grow indoors, it is a whole other story.

Indoor grow rooms offer a lot of advantages, they give complete control over many factors including temperature, lighting and humidity. The one thing they aren’t so good at is naturally dissipating smell. If you do not take the proper precautions, not only will your whole house smell, but it also will seep outside, reaching your surrounding area. There are many ways to deal with this, but the best and most fool proof is to use an active carbon filter – it is what you need if you are serious about odour control.

WHAT IS AN ACTIVE CARBON FILTER?

An active carbon filter is a cylindrical device that hooks up to your ventilation system. It contain a layer of activated carbon, which air is either pulled or pushed through as it is ventilated from the growing area. As it passes through the carbon, the smell of marijuana is eliminated.

HOW DOES ACTIVE CARBON WORK?

Active carbon is carbon that has been treated with oxygen. It results in a highly porous grade of charcoal that can have a surface area of 300-2000 m²/g. This allows air to pass directly through it, interacting with the exposed area, and binding unwanted smells, chemicals, and particles from the air.

What this basically means in terms of a grow room, is that as long as your ventilation is forcing all air through the carbon filter, and that the carbon filter you are using is of a high enough grade, no marijuana related odours are going to escape – they can be that effective.

Although they last a long time, the carbon within the filter cannot bind odours forever, and eventually it will need replacing. How soon this is depends on how much you are growing, and how often you do it – so bear it in mind.

WHAT ARE THE ADVANTAGES OF USING AN ACTIVE CARBON FILTER?

There are many advantages to be had from using an active carbon filter in your grow room:

• They are by far the most efficient, safest, reliable and effective way to control odour. You will not find a profession or serious grower without one.
• They eliminate odour, not cover it up.
• They are extremely easy to use and install.
• Depending on how much you are growing, a decent carbon filter can last for a very long time.
• There is little if any maintenance required – once they are installed, that’s it until the need replacing.
• Unlike some forms of odour control, active carbon filters present no risk of damage or contamination to your cannabis plants.

SETTING UP A CARBON FILTER

Setting up a carbon filter can be as easy as connecting a filter to an inline fan using some ducting. The filter is present in the grow room, with the fan pulling air through it t outside the grow room. As the air passed through the filter, it is cleaned and then exhausted through the ducting.

If you already have ventilation set up, you can slot one it into the system using your ducting at the right place. They can even be included to be part of a bulb cooling ventilation system, allowing odour control and light cooling to be combined into one larger system. As long as the grow room air is pushed or pulled through the carbon before being exhausted out of the system, it will work.

They are considered so effective by the cannabis growing community, that if you are still smelling marijuana outside of your grow room, you are either using a knock-off brand of filter, or you have an air leak somewhere else.