Running a grow tent hinges on so many factors, top of which is how well you are able to control atmospheric conditions in the tent. This is where having the best inline duct fan for grow tent becomes very necessary, as it performs the basic task of ventilation, which sets the atmospheric condition upright.

A grow tent exhaust fan helps exchange air between the inside of the tent and external environs through a vent duct. The exhaust fan for grow tent is installed at a suitable location along with the vent system, acting as an inline duct booster or simply an exhaust blower for grow tent, depending on how large the vent is, and the overall system design.

Inline grow room fans are important for keeping the air moving (boosting its pressure) in the vent, especially when it has to travel over long distances. This fans could also be an inline duct fan vent blower, all depending on where it is stationed in the vent system. In all, a grow room inline fan is an important component in the design and installation of vent blower for grow tent.

The best inline duct fan for growing possesses some paramount qualities which we recommend you look out for in your search. The major quality, however, is its speed, interpreted in CFM, and is responsible for the difference the best fans for grow tent, and ordinary grow room inline fans.

The best grow tent fans should be able to move the heist amount of air, and in this case, is the Hurricane HGC736590. Its high CFM rating of 1060CFM at maximum speed makes it top for our pick in the best grow tent exhaust blower. Vents can be attached to its inlet and outlet points with suitable steel duct clamps, making it a perfect inch inline duct fan vent. Here is our pick on the other members of the best inline exhaust fan products.

Top 5 best inline duct fan for grow tent

1) Hurricane HGC736590 Commercial-Grade Inline Fan

Best Inline Duct Fan for Grow tent
  • High performance

The most valuable asset of this device is how powerful its motor, and consequentially, its fan is. This motor spins fast enough to attain a 1060CFM air movement, which is very impressive and makes it able to handle whole-house ventilation.

Asides its motor capacity, the blades also spans 12 inches in length, helping the overall performance of the inline duct fan draw in more air as a result. The combination of a fast motor, and 12-inch blade, gives the 1060CFM capacity.

  • Durable and quiet

Inlet duct fans are not exactly mounted in the most comfortable of spaces, or the best environmental conditions, but rather mostly ends up in attics, basements and crawl spaces. This makes them exposed to harsh weather conditions, and to thrive in there, the Hurricane HGC736590 is built with a durable steel housing.

This housing possesses resistant properties, protecting the device as a whole from damages despite the poor conditions. For a fan that moves that much air, it is also pretty quiet, and would certainly not be heard in the house, all the way from the basement.

  • Accessories support

The capacity and overall design of this product allow it to be used with other contemporary air ventilation accessory products. One major example is the carbon filter. Using a filter with this product isn’t going to restrict airflow in any way, but rather a completely unobstructed performance.

Since the product doesn’t come with any form of speed control feature, it can also be used with titian control speed devices, allowing the user to vary the speed according to their preference.

The major downside to this product is that it doesn’t come with inbuilt speed control. Therefore it would always run at the highest speed. We recommend you purchase a titian fan speed controller as a result.

Also, its air inlet side doesn’t come with a mounting design for complete sealing when connecting to the ducts. This allows air to leak through that point, causing many users to use duct tape in remedying the situation.


  • commercial-grade high-performance 12inch blade 1060CFM fan,
  • Durable steel housing, it operates quietly,
  • easy to mount with brackets included in the purchase package,
  • ideal for use with carbon filters and titian control fan speed devices,
  • it operates quiet enough to not constitute a nuisance,
  • comes with required mounting accessories


  • purchase doesn’t come with any speed controller
  • The air inlet intake is not flanged,
  • requiring duct tape for complete sealing,
  • although there still remains a possibility of air leakages.


  • Five-year manufacturer warranty.

2) AC Infinity CLOUDLINE T6, Quiet 6″ Inline Duct Fan with Temperature Humidity Controller

Best Inline duct fan
  • Modern and intelligent design

If you are looking for a fan with all the right features to make the most comfortable user experience, then look no further than the AC Infinity CLOUDLINE T6. With numerous modern and intelligent features, this inlet fan is both easy to use, as well as a very convenient fan to have to circulate the air in your space.

Its intelligence starts with programmable temperature and humidity controller. This controller keeps tabs on both the temperature and pressure in the atmosphere, shuffling the fan’s performance to maintain a user-set level. With this device, you can both monitor and maintain temperature and humidity.

The fan motor is also electrically commutated, giving users complete control over its speed. Therefore, you can easily vary the speed of the motor, depending on different atmospheric situations. Other intelligent features include possessing a timer for precisely limiting runtime, as well as having an alarm system. The parameters controlling all these properties are set by the user.

  • Energy-efficient and quiet

As earlier said, the major advantage of having an electrically commutated motor is that it gives users precise speed controls. Also, there is an extra advantage of being very quiet, compared to other inlet fans. The motor is very efficient too, consuming up to 40% lesser of what it normally would. It barely gives a significant spike in energy bills after a month of use.

  • Auto mode and Synchronous feature

Being smart and intelligent offers several advantages to this product, amongst which is something we tag synchronous features. This quality allows several devices of the same or different capacities (Cloudline 4 or 6 series), to be connected in synchronism.

They can be connected together for a more effective ventilation system by increasing their overall airflow capacity. This device’s intelligence also allows it to run in the auto mode, maintaining ventilation conditions by switching between the ranges 0 – 10 fan speeds.

  • Mixed-flow design

The mixed flow design is a design that protects the fan from external contaminations like dust and liquid. Liquid and dust getting into the motor is never a good thing, and could quickly damage the motor.

Also, the motor is built with two bearings, one on each side, and they allow the fan to keep running irrespective of what physical position it is. This flexibility allows users to position the device in any direction and position, without hindering its performance.

A downside of this product is its auto mode, which works by keeping the fan varying between speeds 1 to 10, instead of simply maintaining a speed necessary for the user’s set environmental condition.

In simple terms, the auto mode only maintains, it doesn’t control (increase or decrease) environmental preference. Also, its 351CFM speed is also very low compared to other inline fans of a similar price.


  • Comes with intelligent temperature and humidity controller,
  • electronically commutated motor allows users to vary fan speed and the fan twice as energy efficient,
  • possesses a timer as well as an alarm system,
  • it comes with all required mounting hardware,
  • operates very quietly,
  • its advance design enables connection of more than one of this device together,
  • the mixed-flow design allows it to maintain airflow even in high static pressure application and highly resistant to dust/ liquids,
  • purchase contains all required mounting options,
  • motor contains dual bearings for allowing users mount in any direction,
  • auto mode.


  • poor fan controller in the auto mode,
  • relatively low speed (315CFM) rating compared to products of similar cost.

3) VIVOSUN 8 Inch 740 CFM Inline Duct Ventilation Fan with Variable Speed Controller for Grow Tent

Best Inline fan for grow tent
  • Aerodynamic impeller

The impeller of this fan has a special aerodynamic design, which helps it move at a 2450 RPM, and consequentially cause an airflow of 740 CFM. This makes it very much suitable for large spaces, and for various use in homes and grows tent. In fact, when used in small-sized grow tents, it might generate too much negative pressure, which may not be good for the plants.

  • Quiet operation and durable chassis

Firstly, as a standalone device, this induct fan operates quietly. This quiet mode is well enhanced as a result of it being coated with sturdy leather, which muffles the noise produced. The leather is factory fitted and covers the whole device, excluding the inlet and exhaust, as well as speed controller.

The covering not only helps with noise but also reduces vibrations created as a result of the motor’s movement. For further quietness, an 8-inch VIVISUN silencer can be purchased separately.

Beyond the padding, the chassis itself is also very durable, made with galvanized steel parts, which comes factory painted too. This material and paint covering helps it resist atmospheric corrosion from humidity since it would be spending most of its time in areas with such conditions. The coupling is tight and precise, eliminating rattling and reducing wear as a result.

  • Speed controller/ connection flanges

Mounted on the motor of the fan is a speed controller, which has a variable knob on the outside of the fan. This allows users to vary the motor’s speed across three levels; low, medium, and high, depending on your need. Also, for easy connecting of the ducts to the fan, its inlet and exhaust sides have built-in flanges, making the process a simple hook and tighten act.

Numerous customers over the years have complained about this fan making rattling noise after a few months of usage. This noise is always as a result of damaged bearings, especially when the fan is not being obstructed to cause such noise. It could be that they got flawed products, or maybe the bearings are simply of low quality.


  • aerodynamically designed centrifugal impeller helps it move air at 740CFM,
  • it operates very quietly, the device is covered with sturdy vegan leather that muffles vibrations and sounds, the device is very durable,
  • the fan is fitted with variable speed controller, flanges on the intake and exhaust for easy connection to the duct,
  • compatible with an optional (purchased separately) 8-inch VIVOSUN silencer to further reduce the noise level


  • numerous user complaints of rattling noise after a few months of use point to cheap bearings in the motor.

4) iPower 6 Inch 442 CFM Inline Duct Ventilation Fan HVAC Exhaust Blower for Grow Tent

Best inline duct ventilation fan
  • Composite blades

This fan wasn’t built with the conventional blades that are commonly seen in products today, but rather composite blades. This blades design greatly reduces noise generated by the fan, as well as overall vibrations produced from running. These composite blades work in hand with a central hub, making the unit very quiet.

  • Zero maintenance

A common problem with fans is that over time, their bearings start to wear off, eventually giving way and causing much noise while running. IPower, however, designed in this device, a permanently lubricated bearing, means it would require zero maintenance as time goes on. This is a guarantee of low noise operation for the period in which it lasts.

  • Easy connection

As earlier said, the fan has a center hub design, taking a smaller inlet and exhaust shape than the whole product itself. This model we are reviewing precisely comes with a 6-inch connector (4, 8, 10, and 12inches are also available), and this connector is designed to make duct attachment easier.

  • Low Capacity

The motor runs at a decent revolution, achieving an air circulation of 442 CFM. Although this is a very good airflow rate, it is hardly comparable to the VIVOSUN product, for example, though they are in the same price category. Its airflow rate is, however, very good enough for small-sized grow rooms.

The fan also lacks a speed controller, which would have to be bought separately if you so desire to have control over its speed.  We recommend you go for the variac model, rather than any cheapo controllers. This is because the cheapo speed controllers, cause this fan to make a loud humming sound.


  • composite fan blades greatly reduce noise and vibrations for quiet operation,
  • permanently lubricated bearings that require zero maintenance,
  • both ends are designed for easy duct connection, mounting kit included,


  • low airflow capacity of 442CFM,
  • the product doesn’t come with a speed controller.

5) TerraBloom 4″ Quiet Inline Duct Fan, 188 CFM with Built-in Variable Speed Controller

Best Inline fan for grow tent
  • Speed controller

With a speed controller attached to this fan, users can easily determine how fast it would run. This speed controller works by leveraging on the maximum percentage of the fan in such a way that it selects a speed in reference to the maximum speed. Basically, you can only vary the speed between 60% – 100%, and cannot go any lower. The speed falling lower than 60% poses a risk of the motor overheating, which could damage the bearings quickly. When operated with the speed controller, however, it makes a loud humming noise that really isn’t pleasant.

  • Easy mounting and maintenance

Contained in the purchase package is all the mounting kit that is needed to get the device up and running. Also, the fan is designed with removable duct ends, with locking tabs, which makes connecting the duct much easier. After connecting the ducts, lock on all sides for a very firm connection. For maintenance purposes, the casing can be removed completely, making it completely easy to carry out cleaning and other routines.

  • Overheat protection

Overheat protection is arguably the most standout feature of this TerraBloom fan. While operating, the protection system keeps tabs on temperature, ensuring that the motor doesn’t run beyond 130 degrees Fahrenheit and keep on running. As soon as it does, it is shut off immediately by this system, preventing an overheat condition that could damage the device. After a while, when the temperature falls to an acceptable level, the fan resets itself and picks up from where it ended previously.

  • Low capacity

Now the Achilles hill of this fan is its speed. Being able to afford only an airflow rate of 188CFM, this fan is too low to be used for even medium sized grow rooms. In fact, it might not do well in some small space grow rooms, therefore unless you have done the math and is sure of performance, you would be better off with something more powerful.

From our statistics, many customers complained about getting damaged within the first few months of use, which is why we can safely conclude that it isn’t all that durable.


  • quiet operation,
  • comes with a variable speed controller,
  • designed with removable duct ends and locking tabs for easier duct connection,
  • the mounting kit is included,
  • removable central assembly to make maintenance easier,
  • overheat protection shuts off the device at over 130 degrees Fahrenheit for damage prevention,
  • it is less expensive than the others,


  • very low airflow rate of 188CFM makes it suitable for small-sized grow tents;
  • it is loud humming when operated with the speed controller,
  • poor durability leaves it getting damaged more often than not,

5 Must have qualities in the best inline duct fan for grow tent

  • Airflow rate:

The airflow rate of the inline duct fan is directly responsible for how much air it would be able to circulate. Represented in CFM, the higher it’s the rating, the better off air movement would be in the room. It is important to purchase a fan that can comfortably ventilate your grow room, creating a suitable atmosphere for your plants.

  • Speed controller:

This is all about flexibility. Instead of having a fan that always runs on full capacity, a speed controller would help you limit how fast it should run.

There are different speed levels, which are all accessible for users to select the most preferred at any point in time. Need the fan to run slower because the atmospheric condition is good? Drop its speed, and if otherwise, increase it.

  • Digital features:

This quality is best portrayed by the cloudline product. It includes temperature and humidity controls, a timer, and the automatic mode.

Each of these features allows users to condition the atmosphere more precisely than a normal fan would. The auto mode comes in handy especially, running the fan independent of its user input and maintaining environmental conditions in the grow room perfectly.

  • Noise level:

This could be relevant or not, depending on where you intend mounting the fan. If it’s closer, then you would most certainly need to consider the amount of noise it produces while operating.

Of a certain, inline fans would sure make an amount of noise while running due to their high airflow rate. However, there are some that are conducive enough for the human ears, while we cannot exactly say the same for others. Go for that quiet product.

Do you need an Inline duct fan in a grow tent?

A fan is one of the most important components when building a grow tent. Grow tents are mostly not exposed to direct atmospheric conditions but rather enclosed in a space where the atmosphere is conditioned to favor plant growth.

A fan, or several strategically positioned fans, would be needed for proper air circulation in the area, without which the plants wouldn’t be able to grow effectively. This air circulation prevents molds and other pest organisms from getting to the plant by bringing the outdoor environment indoors.

How to install inline duct fan in grow tent – DIY method

Before you go on to install an inline duct fan, we trust that you have done proper research, and purchased a sufficient capacity product. If you haven’t, calculate your grow room area, and purchase a fan with proper CFM rating to match.

After that, determine where the fan would be mounted. We recommend mounting inside for more effective air exhaust from the grow room.

  • Step 1:

Start by mounting your fan in that suitable place, which should be somewhere in the ceiling. Make use of mounting brackets or adjustable rope clip handles to firmly hold the fan a few inches away from the ceiling.

  • Step 2:

Connect the ducting to the fan, ensuring that it has as minimal bend as possible. This allows for easy airflow. Also, make sure that the duct is not too long or allows light into the grow tent that is meant to be light proof. Make U-bends to take care of light problems.

Do well to seal the point which the duct enters the tent too, or risk pest and other destructive animals going through.

  • Step 3:

Confirm all your connections are in order, especially the inlet and exhaust points of the fan, after which you connect the power cord to a supply.

How do you connect an inline fan to a carbon filter?

Connecting a carbon filter to the fan is pretty easy. Firstly, while following the process for connecting the fan above, mount the filter at the intake of the fan so that the fan is pulling air through.

We recommend you mount the filter indoors only, except it is too big to stay in. This is because air drawn from indoors is cleaned immediately by the filter, causing it to move slower and hence increasing the overall cleaning effectiveness.

Placing the filter at the external end of the venting system causes air to be pushed too fast through it, which greatly reduced its overall cleaning effectiveness.

Final words on the Best inline duct vent blower for grow tent

With all the modern and intelligent features possessed by the AC Infinity CLOUDLINE T6, one would expect it to topple the other products, however, we wouldn’t place it in the first position. This is largely due to its relatively poor airflow rate of 315CFM, which ultimately lets the product down.

We would place the Hurricane HGC736590 as our most recommended for you. Although it isn’t nearly as modern or intelligent as the cloudline T6, its airflow rate is almost three times faster. The basic task of an inline duct fan is to move the air, and this product more than excels at it at 1060 CFM, and blades spanning 12 inches in length.

The cloudline T6 is the next best. It possesses a speed controller, with numerous digital functions like temperature and humidity controls, auto mode, timer, and an alarm system. Using the product is surely going to give the best user experience amongst all others.