FREE Delivery Over £50*

ClearPay - Pay in 4

Best Price Guarantee

Excellent Excellent 5 star yotpo rating

Chat to an Expert

Air Circulation… 9 Ways to Use Your Fans

9 Quick Tips to Maximise Grow Room Air Circulation

Alex Grady

Use them wisely and your air circulation fans will be your new best friends.

They don’t cost much but make a big impact on your climate. Here's how you get the best out of yours.

Why Use Them?

Air circulation fans constantly move air so that you don’t get microclimates – where the temperature, humidity & CO2 level throughout your growing area vary.

  • Reduces chances of mould in hot, humid spots
  • Gives you an even temperature, humidity & CO2 level

On top of this, air circulation fans toughen plants up by creating an artificial wind. This mimics outdoor conditions where:

  • Plant stems and leaves move gently in the breeze
  • This forces them to become stronger over time

1. Mix Your Air (ideally with a DiffuseAir)


All air circulating fans mix air, but some are better than others.

A DiffuseAir is by far the best to use. They mix air without creating any harsh air streams that can cause windburn.

There are two ways to use them:

  • Mix air in your grow room: Attach to RVK and suspend
  • Evenly disperse intake air: Attach to an RVK intake fan

Either way, you free up floor space.

2. Point your air circulators towards a wall or ceiling

point to walls

Try not to point them directly at plants – this can dry them out and/or cause windburn.

If you have any other fan, be very careful to place the fan on the floor and blow air upwards, to ensure the temperatures at the top and bottom of your growing area are more even.

3. Now and again, move your air circulator fans about

move your air circulator fans about

Unless you have a DiffuseAir, it’s unlikely that the first home you give your fans is 100% perfect. To get complete coverage, rehome them from time to time.

Otherwise you’ll end up with pockets of static air, which can eventually cause problems.

4. Don’t think bigger is better

Don’t think bigger is better

You’d be forgiven for thinking a big air circulation fan moves more air than smaller ones. This isn't strictly true.

One big oscillating fan may not reach certain areas in your grow room. Use a combination of smaller supplemental fans to create constant air movement throughout your growing space.

5. Use clip-on fans to reach nooks & crannies

Use clip-on fans

All grow rooms have awkward little corners. You’ll likely find that these areas are hotter and more humid than others in your grow room.

The solution’s a simple one – use a 6 Inch Clip-On Fan. They’ll fit just about anywhere. They're also good for the spot cooling of lights and tanks.

6. Prevent bud rot in flowering

Prevent but rot in flowering

If your humidity is too high during flowering, you can get botrytis (bud rot). Air circulator fans will keep the air moving around your fruits and flowers and will help prevent conditions where bud rot develops.

Make sure you closely monitor the environment with an Grow Gadget Temperature & Humidity Meter. Adjust your fan settings if relative humidity starts to creep up or dip.

7. Use them to cool your nutrient chiller

cool your nutrient chiller

Some grow room tools, such as nutrient chillers, give off heat.

You can point your fan directly at them to keep them cool and optimise your performance.

8. Direct humidifier mist over the plant canopy

Direct humidifier mist

If using a humidifier, you want to make sure you get an even humidity across your growing area.

Point an air mixing fan at the mist coming out of your humidifier. This'll ensure the humidifying effect is constant across your growing space.

9. Run fans 24/7 to prevent problems

Run fans 24/7

When lights go off, your relative humidity naturally starts to climb and you can get some condensation on plants or your canvas. When this happens, bud rot and powdery mildew are more of a threat.

To prevent excess moisture building up, keep air circulator fans running 24/7.

Leave a comment

Please note, comments need to be approved before they are published.