The Best 3 Grow Room Ventilation Setups for Optimal Hydroponics

Environmental controls

Grown room ventilation systems are an essential component of hydroponic gardening. Without them, the plants wouldn’t be able to grow healthy. It is especially crucial if your room is having a hard time with heat and humidity.


Here are the reasons you should ventilate your grow room:

  • Ventilation removes excess heat from the room.
  • Ventilation will control the humidity produced by the plants and devices.
  • Ventilation prevents pests and diseases from spreading through your system.
  • Ventilation controls the CO2 levels.
  • Ventilation also manages wind stress.


In this article, we take a look at the best grow-room ventilation setups and how you can install them.



1. Basic Grow Room Ventilation Setups


The basic ventilation setup for a grow room is affordable and easy to install. All you need is an oscillating fan or an air extractor. The number of fans required will vary depending on your room’s size. You should also consider how hot it can get with the hydroponic system and lights working full-time.



Multiple Small or Oscillating Fan System

Grow Room Ventilation Fan
Fan, Source


Let’s begin with what many consider the cheapest and easiest-to-setup option for grow room ventilation. This option uses several oscillating fans to cool down the room, generate airflow, and keep the plants healthy.

One of this system’s benefits is that you can move the fans around as much as you like until you find the perfect spot for them. Some oscillating fan models are so easy to set up that you’ll only need to find the right location.

They are cheap and highly effective, meaning they will ventilate your grow room at a constant rate.


Tip: You can find fans of different shapes and sizes, but to keep your grown room ventilation effective, you should try to find a 6” diameter fan. This fan size will provide you enough power to keep your grow room ventilation on the right track.


Steps to setup your oscillating fan system:

  1. Find out the dimensions of your grow room.
  2. With the measurements, you can decide the number of oscillating fans you’ll need. Two is the minimum number for most grow rooms.
  3. Pick the right spot for your fans and set them up.
  4. Turn them on and check the temperature and air circulation of your room.


Tip: Avoid pointing your fans directly at the plants as it can produce windburn.



The Air Extractor System

The air extractor system is still affordable and easier to install than other options. However, it might be a bit more tricky than the fan system. The system will pull out the old air, helping cool down the room. By doing so, you are allowing air to circulate inside the room, and that will prevent the spread of diseases in your hydroponic system.


Set up your extractor to replace the air in the room every minute if possible. If that’s not possible because of your extractor’s power, try to replace the air at a maximum of every five minutes.

Additionally, for your extractor to function correctly, it needs to be the right size and power for your room’s size.


Calculating the right strength for your extractor’s fan: All fans are rated by CFM, which means cubic feet per minute. To calculate the fan strength you need, you’ll need to know your room’s size and exhaust efficiency.

You need to keep in mind that you need to extract more air than you let in. If not, you risk filling the room with a lot more air than your plants need. That can be harmful to the integrity of the plants and the entire system.



2. Passive Intake Grow Room Ventilation System 


Any method that does not use a fan to blow air into the grow room is a passive intake system. For instance, the oscillating fan system is passive because it relies on negative pressure inside the tent or grow-room. The air inside the room must have a lower pressure than the atmosphere surrounding it.

Passive intake uses a hole in the room or grow tent. The hole allows air to come in and out, thanks to the negative pressure inside. Depending on the size of your room, you can use more than one intake hole.



3. Active Intake Grow Room Ventilation System


On the other hand, active intake systems work with two sets of fans. The first set draws air out, and the second draws air in. Using a fan to draw air in makes the grow room an active intake room because you actively draw air in and out.

Like with the passive intake, you can have more than one fan drawing air in, depending on your room’s size. We recommend this type of intake if your grow room is bigger than average.

As a rule, you should keep your intake fan on for around 15 minutes and off for 45. Do it hourly, meaning that through the day, you’ll need to turn the fan on and off every 15 and 45 minutes. If your plants need a particular ventilation setup, you can adjust when the fan is on and off.


Tip: To keep your grow room healthy and cool, you’ll need to control the humidity, CO2, temperature, the phase of your plants, and the O2. Understanding these parameters and their importance will help you understand the ventilation needs of your room.


Intake Fan Strength

Knowing your fan’s strength is essential to understand how effective it will be for your grow room size. All fans will have this information in the box, and you only need to divide the fan strength by four. Once you have the result of that division, you’ll know how effective your fan will be for your room size.

  • Strength/4 = square Meter of effectiveness.




Grow room ventilation is as important as any other component in your grow room. Without the proper ventilation, you risk spreading diseases to your plants and harming them by not controlling the room’s humidity or temperature. Hydroponic systems and lights produce heat, and without a way to cool them, they can malfunction over time.

Overall, you can choose between having a passive or active ventilation intake. Ensure that you pick the right one for the type and size of the room you have.



Picture of Kate Beverage

Kate Beverage

I'm Kate, I worked in the DIY/home improvement field in Australia for almost six years. During that time, I cultivated an interest in indoor and outdoor living, with a particular interest in gardening and landscaping. I am passionate about living surrounded by nature and greenery, eating fresh fruit and vegetables, and minimizing my impact on the environment.