Beginning growers always want to skip the fans.
I was the same. I figured I could just use whatever fan I already had lying around and stick it in my grow tent.
And it can work. But it’s usually not enough.
All but the smallest grows need both an inline fan and an oscillating fan. At a minimum.
The good news is that even the best fans for your grow tent are not overly expensive. You just have to know which models represent good value.
And more importantly which ones you should avoid at all costs (hint: most of them).
Let’s dive right in and get started with a quick comparison of the top oscillating fans on the market.
Why do we need fans in grow rooms?
We have created an extraction system with fans that removes humid, polluted air and circulates fresh, clean air throughout our growing areas. A good fan plays a big role in the ventilation of the grow room, its main function is
Increase fresh air exchange: Fresh air can become depleted over time and can lead to a buildup of toxic gases, or the air may not have enough oxygen or other gases needed for plant growth.
Increased CO2 concentration: CO2 is required for plant nutrient cycling. The cycle provides much-needed carbon dioxide for photosynthesis.
Regulates the environment, including temperature and humidity: Growers use LED lights to mimic natural environments. Although LED lights generate the least amount of heat, it still needs to be managed. The temperature in the grow tent must maintain the optimum temperature for plant growth. The same goes for humidity, plants release a certain amount of water throughout the day. If left unchecked, it can cause pests and diseases.
Simulates wind-flow environments to increase plant strength: Plants can accumulate dust and other debris on their leaves, causing reduced gas exchange and blocking much-needed light.
Keep Fungal Diseases, Mold, and Insects Away: Air circulation keeps plants healthy. Without wind circulation, the potting soil will remain damp and can become a hotspot for fungus, mold, insects and bacteria.
ECO Farm 6 Inch Clip Oscillating Fan Fit for Grow Tent with 3-Speed Control
Features:
This ECO Farm wall fan is ideal for a small grow tent, which is why it is our top pick. When it comes to changing the air in and out of your grow operation, you don’t need something blowing with gusto. While this product isn’t made specifically for growing, if you just need something to keep things moving, this fan is wonderful for that. It is small, so it fits easily in your growing area, and if you are growing a large amount of product, you can buy several of these fans and they won’t get in the way or cost you a fortune. This model has a versatile mounting system, so you won’t have to fuss too much with where you put it in your tent. There is also a clamp, so you could just clamp it onto the container that your plants are in. Not only is this fan small and flexible, but it is also quiet, which is crucial for your peace of mind.
AC Infinity Cloudray A6 Circulation EC Fan
Features:
The newly designed next-generation clip-on fan provides precise air circulation for all stages of plant growth. Utilize the cutting-edge EC motor with PWM control to access a wide range of fan speeds, from breeze to powerful airflow. Designed with an EC motor to provide precise air circulation for all stages of plant growth. Numerous 10 speeds, from gentle breeze for seedlings to strong airflow for flowering. The IP-44 rating is designed for use in growing environments and resists high humidity and heat.
Secret Jardin Monkey Fan 16W 7.5’’
Features:
Secret Jardin Monkey Fans are great for airflow and are resistant to the humid environment your grow room provides. This pole-mounted fan is designed for grow tents and rooms, making this clip-on fan ideal for moving air without taking up the space you need. The fan blades are surrounded by a metal grid that’s too small to reach with fingers. This Monkey Fan is designed for tents with pole lengths of 0.63–0.83 inches as well as PVC (commonly used to stretch lattice on canopies).
Growbuds 6 Inch Grow Tent Oscillating Clip-On Fan
Features:
Made with the highest quality materials, specifically designed to fit on grow tent poles to perfection and oscillate smoothly, the Growbuds Clip Fan will become your favorite and will keep circulating fresh air in your grow room for years to come. Specifically made to be compatible with ALL grow tent pole sizes, these fans don’t slide down the pole. Triple 6.3-inch spiral fan blades are angled to deliver efficient airflow with high and low settings to keep your ladies fresh and comfortable. A sturdy, lightweight mesh exterior protects the fan blades and the fan’s surroundings from damage. High-quality components keep this fan running whisper-soft.
Features:
Space-saving design is ideal for your greenhouse, kitchen, office, nursery, and more — any area where space is limited and air circulation is desired. The spring-loaded plastic clip won’t mar surfaces and the adjustable head directs airflow where you need it. It features durable plastic blades and the easily removable safety grill makes cleaning a breeze. The sturdy, compact fan is ideal for circulating air in grow tents for even temperatures and improved ventilation.
What size fan do I need for my grow tent?
To determine the size of fan you need to push out air for your grow tent, you will need to calculate the volume of your grow tent in cubic feet by multiplying the length, width, and height. Once you know the volume, you can determine the fan capacity needed to change all the air in the tent in one minute. Fan capacity is measured in cubic feet per minute (CFM). For example, if you have a 5x5x6.5 foot grow tent with a total volume of 162.5 cubic feet, you would need a fan with a capacity of 162.5 CFM to replace all the air in the tent in under a minute.
The table below shows recommended fan sizes for common grow tent sizes:
• For airflow below 205 CFM: 4″ fan
• For airflow below 402 CFM: 6″ fan
• For airflow above 402 CFM: multiple fans
It is important not to oversize or undersize an inline fan, as this can lead to inefficient ventilation systems and increased energy bills. If you already have a properly sized exhaust fan in your system, you can usually reduce the size of an inline fan by about 20–30%.
There are two types of fan settings available for grow tents — passive and active. Passive setups use just one inline fan to exhaust hot air from your grow space, while active setups use both an inline exhaust fan and an oscillating clip-on fan for better air circulation.
Conclusion
So, these grow tent fans are a must-have for grow facilities. They keep the environment inside your tent clean, ventilated and free of pollutants. They also keep an eye on your outside environment by filtering the smell of your grow unit before they run out. These kits can also be used to draw in fresh air as well as to expel fresh air, and you can set up a great setup by using these kits for intake and exhaust.
The above products are great value for money, allowing you to invest the time in growing them, and they will perform to your satisfaction.