Proper odor control can be a very important part of any indoor garden. There are a few major methods that growers use to manage the odor produced by their garden. Depending on the type of plants you grow, you may not want the odors produced to escape your grow room. For example, lemon sage and castor beans are very fragrant. We hope this guide will help you select the correct odor management system for your grow room.
There are many methods available for controlling odor, the most popular of which is a carbon filter. A carbon filter is a round, hollow device with a membrane that contains activated charcoal (carbon). Dirty air passes through the carbon filter and clean, odorless air exits the other side. Carbon filters are the most popular odor control option on the market because they are highly effective, widely available, low priced, and low maintenance.
Activated charcoal is so effective because of its high degree of micro-porosity, just 1 gram of activated carbon has a surface area in excess of 500m2 or about one tenth the size of an American football field. Carbon filters are a generally low maintenance, with a proper pre-filter you will only have to change your activated carbon every 12 to 18 months. This can vary depending on variables such as fan speed, hours of use, carbon quality, etc.
One of the most common questions about carbon filters is “How often should the air in the grow room be exchanged?” While there is no exact answer to that question, and chances are you will find different answers depending on who you ask, a good rule of thumb is that you should try and exchange the air in your grow space every 5 minutes.
To determine what size fan you will need in order to exchange the air every 5 minutes, simply multiply the width times the length times the height of your grow space. This will give you the total cubic feet of your grow space. Take this number and divide it by 5 to determine the cubic feet per minute (CFM) rating that your fan will need.
For example, if your grow space is 6 feet tall, 6 feet wide, and 6 feet long, it contains a total of 216 cubic feet. To filter this area in 5 minutes, you would need a fan with a CFM rating of 43. We recommend buying a fan that is rated higher than the bare minimum required, as the filter and air ducts will cause a slowdown in the overall air flow.
Many growers use a combination of timers and temperature sensors with their fans. This allows them to turn the fan on at certain intervals, or when the temperature inside the grow room exceeds a certain level. If your fan is too powerful then you can always use a fan speed controller to adjust it to suit your needs.
Ozone generators are one option for odor control, although they are less popular than carbon filters. They remove odor from the air by oxidizing airborne pollutants; The oxidizing agent created by the ozone produces the sweet smelling air often associated with a rain storm. This distinct smell can sometimes be noticeable outside of your grow room.
Ozone is classified as a toxic gas by the EPA; It can damage the lungs, which can cause chest pain, coughing, throat irritation, and shortness of breath. It can also worsen respiratory diseases such as asthma, while also compromising the ability of the body to fight infections. In-home ozone producing air purifiers are banned in the state of California.
You should be cautious when using an ozone generator, not only because they can be bad for your health, but they can also be bad for your plants. If you use too much ozone in your grow room then your plants could end up having no odor at all, they may taste funny, and they could potentially be damaged or killed. Also, ozone is bad for the environment. In our opinion, we do not think ozone generators are the ideal choice for odor management.
Odor Masking Agents
Another popular choice for masking odors and freshening up grow rooms are odor masking agents. These odor masking agents generally come in gel, liquid, or solid form. Growers usually place the masking agent outside the grow area, or just within the grow area near the exhaust vent. Odor masking agents are typically used to supplement other air filtration systems, although they are occasionally used by themselves for smaller grow boxes.
One of the most popular choices for odor control is a product called “ONA” or “Odor Neutralizing Agent”. ONA has become a popular choice among hydroponic growers over the last few years. It comes in 5 different forms, solid, oil, liquid, aerosol, and gel - for application to solid, liquid, and airborne odors. We highly recommend the full line of ONA products for hydroponic growers.
Picking the Right Odor Control System
Choosing the right odor control system is crucial when planning your grow. If you will be growing odorous plants in a larger grow box or grow room, then we highly recommend using a carbon filter. Carbon filters are arguably the most effective way to eliminate unwanted odors, plus they work with any size grow room.
Odor masking agents are a good way to supplement your odor control devices. They can be effective when used with small grow boxes, but they become ineffective and cost prohibitive for larger grow rooms.
No matter how odorous your plants are or how large your grow space is, we have the right odor control system for you. Feel free to contact us if you have any questions about odor control for your hydroponic system, we would love to help!