How to Reduce Odour in Your Indoor Crops

The amazing fragrances emanated from cannabis plants are appreciated by growers. However, there are circumstances when reducing plant odors may be necessary. Here we cover the main methods to dampen that amazing cannabis smell.

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First, reducing the actual terpene profile responsible for the cannabis odors is not recommended, because it impacts the quality of the final product, and nobody wants that.

Removing withered leaves and keeping the grow room clean will help to remove some of the odors. Standard cleanliness practices are also recommended to reduce the likelihood of diseases and pests infesting the plants.

The cannabis plants exude strong odors when the buds are fully developed during the flowering phase because that’s when the terpenes really kick-in. Choosing a fast flowering strain like Sweet Gelato Auto® (SWS76) will minimize the timespan of when the plants smell the most.

Indoor grow rooms should be sealed as much as possible because the odor can escape through the cracks. One must ensure that the space between the tent and the intake/exhaust fans are properly sealed. If the grower is not using a tent, all the walls including the floor and the sealing should be inspected for any cracks or openings, and sealed.

Choosing a correct strain which doesn’t exude strong odors is not a great approach, because the amount of odor greatly depends on how the plants are treated, and the phenotype they develop. Also, if containing the odor is something important for the grower, they will need to use filtering methods or odor neutralizers anyway.

Now that we’ve covered the basics, let’s move onto carbon filters.

Carbon Filters

Carbon Filters

The most common method of removing cannabis odors from a grow room, is by using a carbon filter. Terpenes and various other particles from the grow room attach to the active carbon particles present in the carbon filter, efficiently removing the odor. Before purchasing adequate carbon filters, which cost around €100, a couple of things need to be considered.

Carbon filters can push through a limited amount of air through them, defined by CFM (cubic feet per minute). If the exhaust fan runs through more CFM than the carbon filter, the filter will be bottlenecking the exhaust fan, which is not a good idea. For example, if the carbon filter runs 800CFM and the exhaust fan runs 900CFM, the carbon filter will not function as intended

One must also ensure that the diameter size of the exhaust fan and the carbon filter match, making the gap between both devices easy to seal with ducktape.

There are two main types of carbon in carbon filters, pellet or granulated carbon. Cannabis growers usually prefer granulated carbon because it catches more particles, weighs less, and can contain more odors than carbon filters that use pellet carbon.

Pre-filters are white cotton-like blankets wrapped around the carbon filter which capture all the larger particles without them clogging the carbon filter. Most growers exchange those pre-filters after around 1 year of use.

Carbon filter can be placed both before or after the exhaust fan, however, most growers prefer to place them before the exhaust fan. These filters are also good at removing dust particles, mold spores, and other undesirable entities polluting the grow room.

Ozone Generators

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Another way to remove odors is by using an ozone generator. It’s most often used in larger indoor spaces by expert growers. These generators create ozone, oxygen molecules comprising three oxygen atoms instead of two. Ozone is not recommended to be used with plants because it can cause serious damage.

Ozone generators, when used in an indoor space for odor control, are placed in the exhaust system. One could use a corona discharge ozone generator in the exhaust system, however one must take precaution because this type of generator produces nitric acid, which is not healthy for plants or humans. UV ozone generators can also be used in the exhaust system, however one must engineer the exhaust so that the generator has enough time of contact with the odor-filled air to effectively remove the odor. Basically, if possible, a carbon filter should be considered as the first option.

Odor Neutralizers

Let’s move on to odor neutralizers. They should never be used in the grow room as they alter the smell and flavor of the plants. However, odor neutralizer can be used in a room where the grow tent is placed, as long as the air is not breathed into the tent through the respective room. That’s the best way of removing the smell outside of the plant ecosystem.

Conclusion: Remove That Sweet Smell

Basically, there are three main ways of removing cannabis odors from the grow room, by using carbon filters, ozone generators, or odor neutralizers. Carbon filters are the easiest, safest, and the most practical systems that can effectively remove the vast majority of odor-generating particles, in your average indoor grow room.

Sweet Seeds S.L is not responsible for the misuse of the information contained in this article. Cultivation of cannabis may constitute a criminal offence or administrative misdemeanour; please refer to the legislation on cannabis in your place of residence. Sweet Seeds S.L. does not intend in any case to incite non-legal practices.


Texto: @Sweet Seeds®