Here are the fans you’ll need for your grow tent:
- Exhaust fan: 4″, 6″, or 8″ inline fan with carbon filter
- Intake fan (advised for grow tents 4×4 foot or larger)
- Above canopy clip-on fan
- Below canopy fan
An inline fan with a fan controller lets you dial in the proper ventilation rate. Aim to exchange the air in the tent once per minute. For example, if your tent is 4x4x7, you’ll need to exchange 112 cubic feet of air. To work properly try to minimize duct length and avoid lots of sharp turns, which reduce efficiency.
- A 4 inch inline fan is perfect for small tents up to 4’x4′.
- Use a 6 inch inline fan for medium sized tents such as 5×5, 4×8, etc. Also good for air-cooled lighting.
- An 8 inch inline fan is best for larger grow tents, such as 8×8, 5×10, etc.
AC Infinity makes quiet, powerful fans and are our pick for the best inline fans for grow tent exhaust. The AC Infinity 6 inch fan with speed controller is the perfect fit for most grow tents. Pair with a 6″ carbon filter to remove odors.
You’ll need small inline fans to ensure adequate air intake in your grow tent. In smaller tents, passive air intake may suffice using the tent’s ventilation panels. But this gets tough during flowering, when you need to seal those panels to make things light-proof.For tents 4×4 or 5×5 use a 4″ inline duct booster fan (or a 6″ or 8″ for larger tents). Duct booster fans are noisy and less powerful — but cheaper — than full-size inline fans.
Air-cooled lighting fans
You can use a single inline exhaust fan to push air through your grow light while also exhausting air. Or you could use a separate 6 inch or 8 inch inline fan dedicated to your air cooled light fixtures, with a separate fan for ventilation.
Circulation fans should provide a steady, even breeze throughout the tent. You want leaves to lightly rustle. In smaller tents a single clip fan can do the trick. In larger tents, use clip fans above the canopy and air circulator fans below the canopy.
Above the canopy
A cheaper option is the Hurricane 6″ clip fan, which is about the same price as the slightly less powerful 2 pack of Comfort Zone 6 inch fans. We’ve used all of these brands several times each over the years and have been satisfied with each.
Inexpensive air circulator fans such as the Amazon Basics 7″ fan (or their 11″ fan for larger tents). We’ve also used the Honeywell TurboForce air circulator fan for below canopy circulation. Both are powerful enough for tents up t0 5×5 feet.
Larger tents could use the Vornado mid-size air circulator fan.
You can also use clip on fans in grow tents for under-canopy circulation, but they’re generally less power for the money compared to air circulator fans.
You need to have the following fans for your grow tent:
- Inline fan for exhaust ventillation
- Small inline fan for air intake (optional)
- Fans for air circulation
Your goal is to keep a consistent environment at the proper humidity and temperature levels by using constant ventilation and air circulation to bring in fresh air while avoiding stagnant pockets of damp, stale air.
Learn more about grow tent fans
- Grow tent ventilation setup
- Grow tent fan reviews
- Find the quietest inline fan
- How to set up a 4×4 grow tent
- What sized fans are needed for grow tent air circulation
We hope you find this information useful to learn what fans you need for a grow tent. Setting up your tent properly will ensure you can create an ideal environment for growing cannabis plants.