# What Size Fan Do I Need For My Grow Tent

## What Size Fan Do I Need For My Grow Tent? (With Handy Table For Common Sizes)

First and foremost, the bad news. It’s possible that you’ll have to conduct some math. The good news is that It’s a simple piece of mathematics. And we’ll take you step by step through the process. In addition, we’ll provide you with a useful table that lists the most typical grow tent sizes and configurations. Chances are you will be able to find your information in the table and will not have to perform any calculations.

## What Size Fan Do I Need For My Grow Tent?

It is not the size of the fan that is crucial. It refers to the capacity of the fan. First and foremost, you must determine the amount of capacity you require. The capacity, in turn, dictates the size of the fan. For the majority of home gardeners, a 4 or 6 inch fan would suffice. How do we determine the amount of fan capacity you require for your grow tent’s fan? By following the steps in the computation we’ll go through later. Alternatively, you might scroll down to our table and see whether your tent size is listed there as an option.

### Calculating Base Fan Requirement For Your Grow Tent

Obtaining the overall volume of your grow tent is the first piece of information you’ll need. To obtain this, simply multiply the width by the length by the height (width times length times height). For the sake of this computation, we are using feet rather than cubic feet per minute since fan capacity are measured in cubic feet per minute in the United States. It makes no difference whether or not you utilize meters in your calculations. Consider the following scenario: you have a 5 by 5 foot grow tent with a height of 78 inches, or 6.5 feet.

1. The total volume is equal to 5 x 6.5 = 162.5 ft3.
2. The capacity of a fan is measured in cubic feet per minute (cfm), which is an abbreviation for cubic feet per minute.
3. For the most part, we recommend that you strive to refill the air in the tent once per minute.
4. Using this formula, divide the entire grow tent volume by two or three to obtain the base fan capacity you want.
5. Not so fast, my friend.
6. If you simply have one fan extracting air and nothing else, the capacity we offer is the minimum amount required.
7. In addition, there are variables that raise the capacity requirements.

### Adjusting For Ducting, Filters, Lights, Etc.

Components such as ducting and filters all contribute to a reduction in the capacity of your fan. You must take this into consideration in your calculations and purchase a fan with greater power to compensate for the drop in airflow. Other components, such as lighting, can enhance your cooling requirements. You’ll need to build in some extra capacity to accommodate them.

If your tent is going to be in a hot environment, you should also include some extra capacity. Here are some of the most typical components and considerations to consider, as well as the impact of the additional capacity you’ll wish to add, expressed as a % increase in capacity.

• Lights: a 10% rise for each additional grow light
• Filters: a 25% increase for each additional filter
• Ducting: a 1% increase for each additional foot of ducting
• Bending of ducting: 30 percent for every 90-degree bend (15 percent for every 45-degree bend)
• External heat: If your grow tent is located in a warmer area (e.g., the attic or a sunny room) and/or is not adequately insulated from the external environment, the temperature will rise by 10%.

Add together all of the percentage increases to obtain the overall % increase. Consider the following scenario: we have a single grow lamp, one filter, and 6 feet of ducting with one 90-degree curve. However, the tent is not situated in an exceptionally hot environment. Growth lights add 10% to the total percentage increase, which is 25 percent to the filter and 36 percent to the ducting and bend. The total percentage increase is 71 percent. Then you’ll want to convert this percentage to a decimal and multiply it by one hundred.

• A 44 percent rise would result in a 1.44 percent gain.
• As a result, a 125 percent rise would result in a 2.25 percent increase.
• As a result, 5 percent would be 1.05 percent (and not 1.5, which is a 50 percent increase).
• In our example, that was 162.5 cubic feet per minute.
• In our case, the required capacity is 162.5 cfm multiplied by 1.71 to equal 277.875 cfm.
• However, it is typically a good idea to get a fan that has around 25% greater capacity than you actually require.

### Get A Fan With More Capacity Than Required

We strongly advise you to get a fan with a larger capacity than you require. Running fans at full capacity puts greater strain on them, which means they will not last as long as they should. It also causes them to become louder. When you run a fan at a lower speed than its maximum speed, it will last longer and operate more silently. It also provides the ability to expand capacity in the event that your cooling requirements develop in the future. Nothing can be predicted; a heat wave, for instance, may occur.

Adding 25 percent to our previous example works in the same way as before: increase the capacity by 1.25 times the percentage.

Make a rounding error and purchase the next largest capacity fan of the type you desire.

It has a capacity of 402 cubic feet per minute.

### What Is A Good Fan To Get?

There are many various types of fans available on the market, and the most of them will perform admirably. In general, the more money you spend, the higher the quality of the product or service you receive. This typically indicates that the fan operates at a lower noise level, is more efficient (has a larger capacity per watts consumed), and has a longer lifespan. Our favorite fans are the AC Infinity Cloudline fans. They are neither the most affordable nor the greatest quality. However, they are the most cost-effective option.

The 4 inch fan has a capacity of 205 cfm, the 6 inch has a capacity of 402 cfm, and the 8 inch has a capacity of 807 cfm. In huge tents, you may require more capacity than even the largest fans are capable of providing. This would necessitate the purchase of a number of fans.

### Table Of Fan Requirements For Common Grow Tent Sizes

The fan power (in cubic feet per minute) required for various grow tent sizes is shown in the following table. It is not a problem if the height of your tent is slightly different from the standard height. The capacity that has been provided will still be adequate for your needs. Similarly, if you have a few additional feet of ducting (or a few feet fewer), you may still utilize the closest situation in the table. Because you should be purchasing a fan that can handle approximately 25% more airflow than your requirements, you should have some wiggle room if you find yourself in need of a little more power later on.

1. That means one light for everything up to and including the 55, two lights for the 48 and 510, and four lights for the two largest sizes, respectively.
2. That means the cfm value given is your final number and the one you should look for in a fan.
3. For everything under 402 cfm, we recommend their 6 inch fan.
4. For requirements exceeding 807 cfm, you’ll need to place numerous fans in your tent.

## Do I Need An Intake Fan?

In most cases, an intake fan will not be required for tiny tents. If you have a sufficient number of intake vents or if they are of sufficient size, having only intake vents may be sufficient. Generally speaking, opening intakes should be three to four times the total size of the outtake vents, according to the rule of thumb (s). You might have one enormous intake aperture or three smaller ones that are each as large as the outflow opening, depending on your needs and preferences. If your tent does not have enough, or openings that are large enough, you will need an intake fan to keep the air flowing.

It has the potential to have around 25% less power.

It goes without saying that any ducting and bends in the ducting that are linked to the intake fan should be taken into consideration as well.

In the case of 5 feet of ducting with one 90-degree bend linked to the intake fan, you need to increase its capacity by 30% (25 percent for the bend and 5 percent for the ducting length), therefore you multiply by 1.3 to get the required increase in capacity.

## What Size Carbon Filter Do I Need?

When purchasing a carbon filter, there are basically just two considerations to keep in mind. The first is that the flange size must correspond to the fan size. If you purchase a 4 inch fan, be certain that you also get a 4 inch filter. Second, ensure that the filter’s capacity (also measured in cubic feet per minute) is equal to or greater than the fan’s capacity.

It is recommended that you get filters from the same manufacturer as your fans. For example, if you choose the AC Infinity fans that we propose, they will come with matching filters as well.

## Where To Place Fans And Filters

You have a great deal of latitude in this situation. The first option you must make is whether to place both the fan and the filter inside or outside of the tent, depending on your preference. It is also possible to have one inside and one outdoors. Inside is normally less difficult, but it may not be a choice if you do not have the necessary room. If you’re thinking about placing your grow tent outside, check out ” Carbon Filter Outside Grow Tent “. The fan and filter should be placed at the very top of the tent if they are being used within the enclosure.

In order to pull in colder air, the intake vents (or fans, if you want to use them) should be situated toward the bottom of the enclosure.

## Fan Size For Grow Tent: Final Thoughts

Calculating the proper fan size for your grow tent may appear to be a difficult task, but it does not have to be. In following the guidelines we provided above, you will end up with a fan that is capable of successfully removing any surplus heat from your tent, regardless of whether you have a large grow tent or a little grow tent setup. Most likely, the size of your tent was already included in our table, and you were able to avoid having to perform the calculation. It wasn’t that tough, even if you had to perform the arithmetic (or even if you simply ran through it in your head), since it wasn’t that complicated.

## Grow Room Fan Size Calculator with Size-wise CFM

Grow Room Fan Size Calculator with Size-Wise Results»Home»Environment»Grow Room Fan Size Calculator with Size-Wise Results CFM31702Views0 If the ventilation is too low or too high, it is the same as having dead(almost) grow plants. And the overall ventilation of your grow system is mostly determined by the size of the intake and exhaust fans that you use. So, how do you determine the appropriate fan size for a grow room? To calculate the size of your grow room or tent’s extractor fan, multiply the volume of your grow room (in cubic feet), the carbon filter factor (+25 percent), the insulation factor (20 percent), the length of ducting (plus 10 percent for every 10 feet), and the light factor (plus 10 percent for every 1000W).

• If you want to figure out what size intake fan for grow room to utilize, simply subtract 15-20 percent from the size of the extractor fan.
• Some of you may eventually raise an eyebrow and wonder, “What on earth do these ‘factors’ mean?”.
• Take it easy for a while, dear grower.
• Please allow yourself a few minutes to go through the full text if you are truly interested in learning how the math behind this method works.

## Factors to Consider in Calculating Grow Room Fan Size

First and foremost, let’s define what these parameters are, how they influence the calculation of grow room fan size, and what precise proportion they must contribute to the computation.

### Factor 1: The Volume of The Room/Tent

To begin, determine how much room your fans will have to contend with, also known as the active grow space. Or to put it another way, that is the area illuminated by your grow lights. And, in order to keep things simple, let’s suppose that your fans will be able to completely replenish the air in the room in one minute (explained in the next section). a general rule of thumb Simply take the measurements of your tent (length, breadth, and height) and multiply them together to obtain the total volume.

Without taking into consideration any other considerations, this figure represents the fan CFM that you require.

For example: Fan Size= (10 feet by 10 feet by 7 feet)/1 Minute = 700 CFM; Fan Size = (10 feet by 10 feet by 7 feet)/1 Minute = 700 CFM;

### Factor 2: Time of Complete Air Replacement

When determining the fan size required for your grow room or tent, you must first determine the volume of air that needs to be ventilated each minute of the day. Because, as you may be aware, the size unit (CFM) indicates the amount of air that the fan can move in a minute. a general rule of thumb Calculate the volume of your grow area (length x breadth x height) and divide it by the number of minutes it takes to completely exhaust all of the air in your grow space. According to this example, if the room’s dimensions are 10 feet(L) x 10 feet(W) x 7 feet(H), the total volume will be 700 cubic feet in total.

### Factor 3: Presence of Carbon Filter

A carbon filter inline in the ventilation system reduces the effectiveness of an extractor fan. After passing through a layer of activated carbon, the speed of the air is reduced to a certain level. Additionally, the age, size, and thickness of the activated CO2 layer of the filter, among other factors, must be kept to a minimum. However, for the time being, we will not be including them. a general rule of thumb Extraction fan efficiency is reduced by 25 percent when carbon filters are used. So if you have one in-line carbon filter in your system and your fan has a general capacity of 200 CFM, the actual fan size required is: Fan Size= (200 CFM + (20 percent)) = 250 CFM.

### Factor 4: Insulation of the Room

If you are growing in a well-insulated area that does not experience a great deal of heat exchange with the surrounding environment, you do not need to take this element into consideration. Theattic, basement, upstairs, south-facing bedroom, and other such spaces with less insulation and more exposure to the sun are examples of such regions that need to be taken into mind. In any of these scenarios, the temperature will be either higher or lower than the temperature that you are required to maintain in your grow room.

If the unit is located in a chilly environment, such as a basement, the needed CFM should be reduced by 15%.

### Factor 5: The Ductwork Curves and Length

It should go without saying that ducting bends and length will reduce the air extraction capability of the fans in the system. Depending on the size of your grow room and the quantity of plants in it, there are three possible ducting configurations:

1. Ducting that is as short as possible or without bends
2. The following types of ductingruns are available: medium ductingruns (5-10 feet) with 2-3 bends
3. Long ductingruns (10-20 feet) with 3-6 bends

As a general rule of thumb The fan CFM will increase by 5 percent for every 5 feet of ducting that is installed. The CFM will increase by 20% for every 90-degree angle in the ducting. If you have a 200CFM starting fan size, you need do the following: Consider the following: fan size considering ducting(15′)=(200 CFM + (20015 percent))= 230 CFMF Consider the following: 320 CFM (assuming bends (3) = 200 CFM plus (200-60 percent)) = 200 CFM

### Factor 6: Lights and Other Heat Sources

As you are aware, the two most evident heat sources in a lamp are the lights and the pumps. If you utilize air-cooled lights in your grow room, though, things are a little different. However, if they are not air-cooled, you must account for each of them when estimating the size of your expected fan. The same is true for other heat-generating equipment such as motors and other such devices. As a general rule of thumb For every 1000W of bulb power, increase the fan cfm need by approximately 10%.

## Grow Room Fan Size Calculator(ExtractorIntake Fan)

To complete this section of thegrow room fan size guide, we’ll use a test case of a grow space, imply certain basic circumstances, and figure out the ultimate size of bothgrow room ventilationfans of both extract and intake. Consider the following scenario: we have an 8x8x7 grow tent in your basement, along with an inline carbon filter that is connected to a 4′′ duct system. There are 15 plants to grow in the space since it is large enough for ScrOG type training (according to our size guide).

In addition, except from the light, there are no other significant sources of heat.

### Extractor Fan

Let’s start with the formula for the grow room extractor and intake fan calculator:-

#### Step 1: Calculate the Space Volume

The first step is rather straightforward. All that is left to determine is which unit to use. These standards are divided into two categories, one being the European Standard and the other being the North American Standard. The first type of standard measures the distance in meters (m), whereas the second type measures the distance in feet (ft) (f). For example, let us use the American Standard of measuring as an example. As a result, the tent’s volume will be as follows: Volume= 8 feet x 8 feet x 7 feet = 448 cubic feet

#### Step 2: Calculate The Air Replacement Time

For the sake of argument, let us suppose that whichever fan we end up with will be able to replenish the whole volume of air in the tent/room in less than one minute.

The computation becomes less complicated as a result of this. Fan Size = Volume x Number of Minutes to Empty 448 cubic feet per minute = 448 cubic feet per minute of air (Cubic Feet Per Minute)

#### Step 3: Calculate Carbon Filter Allowance

As previously stated, we have a 4″ carbon filter installed in our setup, which is connected to the ducting system. Furthermore, the precise pace at which it will impair fan efficiency is 25 percent. As a result, the fan size is 448 CFM plus (448 25 percent) = 560 CFM.

#### Step 4: Calculate the Insulation

The amount of insulation in the grow room/tent has a significant impact on the environment in which the plants develop. Consider the fact that we have a grow setup in the basement, which is significantly colder than the other room where it was originally planned to be. As a result, we’ll take a 15% reduction in the needed fan size for the space into consideration. Fan Size= 560 CFM – (560 15%)= 476 CFM Fan Size= 560 CFM – (560 15%)= 476 CFM

#### Step 5: Calculate the Ductwork

When we have an 88 grow tent setup with a grow room ducting fan, we are advised to maintain the ducting to a maximum of 10 feet in length (including the bends). That is not a rule or anything like that, but let us stay with it for the purpose of calculation. There are approximately 2 bends in the ducting as a result of multiple turnings and modifications. As a result, fan size = 560 CFM + (560 10%) + (560 40%) = 840 CFM. Fan size = 560 CFM + (560 10%) + (560 40%) = 840 CFM.

#### Step 6: Calculate the Lights

Lights, which act as heat sources, are meant to increase the CFM need by 10% for each bulb. However, because we use an air-cooled HID lightset, these will not cause the area to become hot. And we don’t have to factor it into our calculations either. Fan Size= 840 CFM + 0= 840 CFMFinally, thegrow room extractor/exhaust fan calculatorrecommends that we choose a fan with a capacity of840 CFM or greater.

### Intake Fan

Are you finished with the calculation of the grow room exhaust fan size? Now is a good time to introduce some fresh air into the grow chamber through the air intake fan. Once you’ve determined the size of your exhaust fan, determining the size of your grow room intake fan is rather straightforward. In the grow chamber, there should be a tiny negative pressure in the air. That implies you have to take in slightly less air than you exhale in order to maintain the same pressure. It follows that the CFM of the intake fan cannot be as high as the CFM of the exhaust fan, for obvious reasons.

So, based on our prior data, the final intake fan size is 714 CFM (840 CFM – 15%) = 714 CFMSo, the final intake fan size is 714 CFM (840 CFM – 15%).

## Quick Recommendations(for Grow Tent)

There are a limited number of grow tent sizes available, and determining the appropriate grow fan size can be a time-consuming procedure. For normal grow tent sizes, we’ll supply you with a fan size that has been calculated in this section of the grow room fan size calculator guide:

### What Size Fan for 2×2 Grow Tent?

In a 2x2x6 tent, there is typically one carbon filter, four 400-watt non-air-cooled lights, no ducting inside, and a passive air intake system for bringing in fresh air.

The fan size for a 2x2x6 grow tent is (24 cubic feet per minute) x 1.25 x (1.2) = 36CFM if you maintain it well-insulated from the environment.

### What Size Fan for 2×4 Grow Tent?

It is common for a 2x4x6 tent to have one carbon filter, four 600W non-air-cooled lights, 3-6 feet of ducting inside, and an air intake system that is passive in nature. If you maintain it well-insulated from the surrounding environment, then-Fan size for 2x4x6 grow tent= (48 cubic feet per minute) x 1.25 x 1.05 x 1.25= 78 CFM if you keep it well-insulated from the surrounding environment

### What Size Fan for 3×3 Grow Tent?

One carbon filter, four 600-watt non-air-cooled lights, 3-6 feet of ducting, and a passive air intake system are all standard features of a two-by-four-by-six tent. The fan size for a 2x4x6 grow tent is (48 cubic feet per minute) x 1.25 x 1.05 x 1.25 = 78 CFM if you maintain it well-insulated from the surrounding environment; otherwise, the fan size is

### What Size Fan for 4×4 Grow Tent?

When it comes to a 4x4x6 tent, you receive one carbon filter, four 600W (non-air cooled) lights, eight to ten feet of ducting inside, and a passive ventilation system. If you maintain it well-insulated from the surrounding environment, then-Fan size for 4x4x6 grow tent= (96 cubic feet per minute) x 1.25 x 1.08 x 1.25 = 130 CFM if you keep it well-insulated

### What Size Fan for 4×8 Grow Tent?

When it comes to a 4x8x6 tent, you receive one carbon filter, four 600W (non-air cooled) lights, ten to fourteen feet of ducting inside, and an active air intake system. If you maintain it well-insulated from the rest of the environment, then- 192 cubic feet per minute multiplied by 1.25 × 1.12 x 1.25 = 336 cubic feet per minute (exhaust fan size for 4x8x6 grow tent). The size of the intake fan for a 4x8x6 grow tent is 285 CFM.

### What Size Fan for 5×10 Grow Tent?

One carbon filter, four 800W lights (non-air cooled), 15-18 feet of ducting on the interior, and an active air intake system are all included in a tent measuring 5x10x8. If you maintain it well-insulated from the rest of the environment, then- For a 5x10x8 grow tent, the extract fan size is (400 cubic feet per minute) x 1.32 x 1.16 x 1.25 = 765 cubic feet per minute. The size of the intake fan for a 5x10x8 grow tent is 650 CFM.

### What Size Fan for 8x8x8 Grow Tent?

When it comes to an 8x8x8 tent, you receive one carbon filter, four 1000W (non-air cooled) lights, 18-20 feet of ducting inside, and an active air intake system, to name a few amenities. If you maintain it well-insulated from the rest of the environment, then- The extract fan size for an 8x8x8 grow tent is equal to (512 cubic feet per minute) x 1.4 x 1.19 x 1.25 = 1066 cubic feet per minute. The size of the intake fan for an 8x8x8 grow tent is 906 CFM.

### What Size Fan for 10×10 Grow Tent?

One carbon filter, six 800-1000W (non-air cooled) lights, 20-22 feet of ducting inside, and an active air intake system are included in a tent of approximately 10x10x8 feet. If you maintain it well-insulated from the rest of the environment, then- 10x10x8 grow tent extract fan size = (800 cubic feet per minute) x 1.54 x 1.22 x 1.00 = 1878 cubic feet (CF). The size of the intake fan for a 10x10x8 grow tent is 1600 CFM.

## Boost Grow Room/Tent Fan Life By Doing These

You should be aware of how critical it is to have a fan in a grow room.

Being a little more cautious about a few things might help to extend the life of these gadgets. Let’s have a look at how-

### Don’t Mismatch Your Ducting and Fan Diameters

Already, ducting is a significant factor in lowering the fan efficiency. The situation becomes much more dire if your fan and ducting have adiameter mismatches, as described above. As an illustration, a combination of a 6′′ fan and 4′′ ducting will result in airflow being slowed. Summary: Make an exact fit between the fan diameter and the ducting diameter when designing your system.

### Induce Active Air Intake Instead of Passive

If you’re dealing with a medium-sized grow room or tent, a few air intake holes will not be adequate to draw in enough fresh air to keep things running well. In order to keep up with the wind pressure and air supply in grow spaces that are higher than 8’8″ or so, active air intake fans for grow rooms should be used. Also, find out how to set up an exhaust fan in a grow room to ensure optimum efficacy and efficiency.

### Use A Centrifugal Fan

Growing in tiny tents or rooms with squirrel type grow fans is an excellent option. Centrifugal fans, on the other hand, are more appropriate for bigger spaces with higher extraction power requirements. The calculations for the grow room fan calculator in this post were all created in this manner, in fact, throughout the whole text. Centrifugal fans are those that are used in conjunction with an air conditioning panel, ducting, and a carbon filter to circulate air. It will filter the air in your home, chill the grow lights, and ventilate the garden air as well as provide other benefits.

You must provide varied levels of air ventilation for your plants depending on their development stage and the season. If we take the vegetative stage as an example, it should be higher than it should be during the seedling period. And a fan speed controller can help you do this. Using timers, some of their more complex models allow for this CFM fluctuation to be pre-programmed in advance. In addition, make certain that the fans have a suitable on-off cycle.

### Protect from Bugs

The inlet/outlet fan is normally situated close to the ground surface of the machine. Because the air near the ground has a lower temperature than the air above it. However, this increases the likelihood of bugs, dust, and airborne diseases entering the building. Maintain the protection of your grow room fan arrangement by installing a bug mesh into the inlet fans to eliminate this hazard. It will also help to lessen the amount of noise generated by the grow room exhaust fan. You have, on the other hand, recommended that you use the quietest grow room exhaust fan available.

## When Exactly You Care About Fan Size?

We know that you, as a dedicated grower, already have an idea of what you want to do next. But let us consider the significance of accurate grow room fan cfm calculation for the time being –

### Growing Plants Demands More Airflow

In the early stages of a plant’s growth, the leaves are less in size than they eventually become. As a result, the amount of CO2 that they absorb from the surrounding air is not that significant. A good wind around the leaves may be able to provide them with the necessary carbon dioxide supply. However, as they mature, their leaves increase larger, necessitating the production of CO2. Photographic activities like as photosynthesis and transpiration are carried out more often. CO2 (for photosynthesis) and oxygen (for transpiration) are becoming more scarce as the climate warms.

As a result, in order to keep plants alive, you must exhaust more of the heavy CO2-rich air and replace it with more fresh air. In order to do this, more powerful and consistent extractor fans will be required, but the passive and active air intake systems will remain operational.

### To Evacuate Excess Heat

A grow system’s primary heat sources include lamps, lights, and pumps, which are all widespread in the industry. They become the primary source of heat and temperature in a closed-off grow room environment. Unless you provide adequate ventilation, they will soon elevate the temperature to 100 degrees Fahrenheit or more. When the temperature rises to this level, plants begin to develop more slowly and are more susceptible to heat stress. Even in the worst-case situation, they may succumb to their injuries.

In addition, the humidity in the grow chamber will rise as a result.

## Final Words

Phew! It had been a long road from the beginning to this point in the post, and I was exhausted. But, by the conclusion of this article, we hope you’ve learnt what to look for and how to calculate fan size for a grow room or any sealed grow environment. Please share your thoughts if you require a customized solution to this issue in your comments. We’ll get back to you as soon as we can with an appropriate response. Best of luck with your growth! I’m Saleh, and I’m a blogger that enjoys doing home improvement projects on the side.

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## Grow Tent Fans – Sizes, Placement, Setup, FAQ (Updated 2022)

It is critical to have adequate circulation in your grow tent if you want to avoid mold and powdery mildew from forming on your cannabis. Throughout this article, I’ll cover all you need to know about choosing an inline fan for your grow tent and how to correctly install and configure it as well. How to choose the right grow tent fan size and power rating, where to install the fan, how to set up your grow tent fan, and what additional accessories you’ll need are all things I’ll assist you with.

### Selecting the proper grow tent fan size and power:

“What is the right grow tent fan size?” is definitely one of the first questions you’re thinking about. as well as “What is the recommended grow tent fan power?” Generally speaking, when it comes to replenishing air in a grow room, the rule of thumb is that you should be able to replace all of the air once each minute. That is the CFM rating, which you will learn more about further down. In order to keep your grow tent cool, the fan diameter will be decided by the CFM (cubic feet per minute) rating that you want.

So don’t be concerned about having the correct CFM rate.

Then there are a few other factors, such as a 25 percent drop in fan power if you include a carbon filter, and a 30 percent loss in fan power for each 90-degree curve in your ducting.

#### The proper size fan for a 4×4 grow tent:

Let me give you an example of how to calculate the area of a 4×4 grow tent, which is a fairly typical size among indoor growers: The majority of 4×4 tents have dimensions of 48 in x 48 in x 80 in. As a result, the total volume of air in a 4×4 grow tent is 4ft (length) x 4ft (width) x 6.667ft (height) = 106.67 cubic feet (4ft (length) x 6.667ft (height). However, this does not imply that you require a 106 cfm fan. When you consider that a carbon filter will lower your fan efficiency by 25 percent, and that one 90 degree duct bend would reduce your fan efficiency by another 30 percent, a fan that produces 215cfm will produce 112cfm (200cfm x 0.7 x 0.75).

#### What size fan is needed for other grow tent sizes?

(Click on image to expand) It is important to note that grow tent inline fans are not made to the precise CFM output you want, thus you may have to go over by 50-100cfm when selecting a fan for your grow tent. I recommend using a fan with variable speed settings, such as the AC Infinity S or T Series, so that you may modify the CFM to meet your precise requirements. Each of the AC Infinity fans listed below has ten speed options, so if you just want 100cfm, you may get the most basic model, which is a 205cfm fan, and run it on the middle speed level to achieve that volume of air.

### Grow tent fan placement:

Depending on where you want your grow tent fan to be, you have two alternatives. It is possible to work either inside or outside the grow tent. What’s the difference between the two? If you pick outdoors, the fan will draw air from the interior of your tent to the outside through a duct located on the top corner of your tent, allowing you to be more comfortable. You’ll want the fan and filter (if you’re using one) hanging near the top portion of the tent, where the warmest air will naturally travel to keep it cool inside.

Hangers are not often included with fans, so double-check that you have them.

If you decide to place the fan outside, you’ll need to figure out how to get it to rest in a comfortable position.

Because of the fan’s ability to produce a low pressure condition within the tent, when air is blasted out, new air is naturally drawn into the tent.

### Grow tent fan setup:

Yes, the diameters of your inline fan and duct will need to be the same at the place where they connect.

##### Passive or Active Air Flow For Your Grow Tent?

The sorts of fan sets you may utilize in your grow tent or growing room are passive and active. Passive fans are the most common. The difference is whether you want air to passively re-enter your grow tent or if you want it to aggressively re-enter your grow tent. Passive grow tent air circulation relies on a single inline fan to evacuate hot air from your grow room, reducing the need for additional fans. When air is forced out of your enclosed grow area, the pressure in the room drops to a negative pressure, which means that air from outside the tent or room should naturally be drawn in via any openings to replace the air that has been forced out of the space.

• If you want to guarantee that the air returning to the tent is being filtered, or if the air returning to the tent is not returning rapidly enough, active grow tent air replacement is the best option for you.
• Simply ensure that you have the right size ducting (which should be the same diameter as your fan), duct clamps, hangers for hanging, and zip ties before beginning (make sure zip ties are long enough to go around the diameter of your carbon filter).
• To install the filter, just attach ducting to the side of your fan that is responsible for sucking in air.
• Clamps should be used on both sides (usually provided).

If you’re using an active air flow configuration, I’d recommend operating both fans at the same speed to ensure that the quantity of air escaping the grow tent equals the amount of air returning to the grow tent.

#### How to install a grow tent fancarbon filter inside your tent:

Attach the hangers to the support bars that run along the roof of your grow tent. You’ll need enough for the fan and the ducting, so plan accordingly. Make sure they’re the right length for the fan you’ll be hanging. Keep in mind that heated air rises to the top of the tent, so avoid hanging the tent too low. 2.Attach zip ties or metal brackets to the attachment area of your grow tent fan: Place zip ties or metal brackets to the attachment region of your grow tent fan. Zip ties should be used to connect hangers.

In order to use your grow tent fan, you must first connect your carbon filter to the intake side of the fan (the side that sucks air in).

You may either connect it directly to the fan or use ducting to attach it to the fan.

Attach the grow tent duct sleeve to the fan ducting by wrapping it securely around it.

#### Other Inline Fan Installation Notes:

The setup is straightforward; it took me no more than 30 minutes to complete my AC Infinity T4 installation. The most efficient design would be to route the duct out a window so that the hot air from your tent does not just blow into the room where your tent is placed, where it would be sucked back in and render the entire operation ineffective. Not everyone has the benefit of having a window in close proximity to their camping site. In that case, if you’re compelled to blow tent air into the same room where the tent is placed, I highly recommend investing in a portable air conditioner to re-cool the air before sucking it back into the tent through the bottom tent windows.

### Does It Matter What Carbon Filter I Choose For My Grow Tent Fan?

When selecting a carbon filter for your grow tent fan, the one thing you want to make certain of is that the diameter of the connection point on the fan and the filter are the same. Make certain that your inline fan is equipped with a four inch carbon filter if your fan is four inches in diameter. Apart from that, there isn’t much of a difference between carbon filters; they’re simply large metal canisters that filter your air through charcoal to remove contaminants and odors from it.

### Do I Need an Oscillating Fan in Addition to my Inline Fan?

Even though the inline fan removes and replaces the air in your grow tent, it performs a poor job of circulating the air. As a result, you should think about including an oscillating fan in your grow tent to keep the air circulating and prevent mold and mildew spores from taking root. It will also aid in the distribution of fresh air for the benefit of the plants. There are little affordable oscillating fans that you can attach into the grow tent poles if you have a look at the fans I’ve listed below.

### Which Grow Tent Fans I Recommend:

As long as you’re willing to purchase the ducts and hangers separately from the fans, AC Infinity offers fantastic grow tent fans. Purchasing the ducts and hangers is simple – simply match the duct diameter to the fan diameter. What is it about the AC Infinity fans that makes them so much superior than the competition? This fan is equipped with a programmable controller, which allows the fan to switch on in response to a range of different scenarios. For example, you may program the fan to turn on when the humidity reaches a given threshold.

2. When my AC Infinity T4 was running at maximum power, I was pleasantly pleased at how quiet it was.
3. This results in the fan motors being loud.
4. Quiet Inline Duct Fans With Temperature and Humidity Control – CLOUDLINE SERIES Them fans are priced similarly to other fans without the technological characteristics, therefore it makes financial sense to purchase one of these instead of another fan.

The fans are available in three sizes: 205cfm, 351cfm, and 750cfm (4-inch, 6-inch, and 8-inch). Click here to see whether they are available on Amazon.

#### VivoHome Inline Fan Kit

If you don’t want to go through the trouble of sourcing all of the components separately, this kit includes a fan, 8 feet of ducting, clamps, hangers, and a carbon filter. It is available in two different sizes to accommodate different grow tent sizes. With this kit, the main drawback is that the fan cannot be programmed to come on when particular conditions are fulfilled, such as a certain temperature or humidity. The fan has a simple on/off switch. Despite the fact that some customers have stated that they are content with the fan running all of the time.

#### Secret Jardin Clip On Monkey Fan for Grow Tents:

Secret Jardin created this 6-inch clip-on oscillating fan with a grow tent owner in mind when they created this product. The clip is designed to attach securely on the support poles of grow tents. The fan will ensure that your grow tent has adequate air circulation, which is necessary to avoid the growth of mold and powdery mildew. I’d recommend using one of these oscillating clip fans in conjunction with an inline fan in order to maintain the ideal growth environment in your grow tent.

#### Keeping Your Grow Tent Cool

When it comes to keeping your grow tent temps under control, you may want more than simply an inline fan. My best recommendation, without requiring you to read the entire post, is to consider purchasing a portable air conditioner for the room in which your tent is placed, or to consider adding CO2 to your growing environment, which allows you to grow a few degrees hotter than usual. See my whole post on decreasing grow tent temps for more information.

### Ideal Grow Tent Temperature and Humidity for Growing Cannabis:

The optimal temperature for cannabis plants is between 70 and 80 degrees Fahrenheit (23 degrees Celsius). Consequently, consider yourself fortunate if you have a modest grow light in a small tent, or other circumstances that allow you to maintain those temps without using an inline fan. During the seedling and vegetative stages of the cannabis plant’s life cycle, 60 percent to 70 percent humidity is ideal. When cannabis plants are in the blooming stage, they grow best when the humidity is between 40 and 60 percent.

As your plants mature, they will begin to use a significant percentage of the CO2 that is available in your growing environment.

#### Other Resources for Growing Cannabis Indoors:

I developed numerous useful lists and tips to assist you in completing your home improvement project the right way, in addition to determining the proper fan size for your needs. The following are some other articles I strongly recommend: Choosing the Proper Size Grow Tent, This Year’s Best LED Grow Light List, and Understanding Grow Light PAR PPFD and Wattage, among others. Last but not least, don’t forget to check out myhome page for a comprehensive collection of useful resources.

### Grow Tent FanCarbon Filter FAQ:

You’ll just need 30-45 minutes to complete this task.

### What should I do if there isn’t a CFM output for my exact grow tent size?

The AC Infinity fans feature a number of different speed settings to choose from.

As a result, if you just want 100cfm, you may get the 205cfm (smallest model) and utilize the middle of the ten available speed settings.

### If I’m buying parts separately, how do I know if they’ll all fit together?

The diameter of all of these components is the same. If you purchase a 6′′ fan, be sure you also purchase 6′′ ducting and a 6′′ filter to complete the installation. That’s all there is to it, really.

### Do I need to hang the carbon filter?

The carbon filter should be placed at the top of your tent in order to capture the warmest air because it is where air will reach your fan from the outside. It would be inefficient to hang the filter low or to place it on the floor, for example.

### Which end of the grow tent fan do I connect the carbon filter?

Connect the carbon filter to the “front” of the fan, which means that the fan is sucking air through the filter rather than expelling air through it, and that the fan is running continuously.

### What size fan will fit in my grow tent?

Most grow tents accommodate 8-inch ducting, while some may only accommodate 6-inch ducting.

### What if the size of my duct is too big for the duct hole on my grow tent?

If your grow tent outlet is 6 inches in diameter and your ducting is 8 inches in diameter, you’ll need to purchase a ducting reducer.

### There’s too much negative pressure in my grow tent

Alternately, reduce the speed of your fan and, if possible, open up the passive air intake windows on the bottom of your tent even more, or consider installing an active air intake fan, which works in the same way as your other fan but is mounted on the bottom of your grow tent and pushes air into the growing chamber.

### Can you wash or clean carbon filters after extended use?

It is possible to clean a carbon filter using compressed air. The filter may be used for up to one year before it has to be cleaned.

### Can you place a carbon filter on each side of your fan?

Yes, although it may result in a slight reduction in the power efficiency of your fan. Check to see if your fan is strong enough to manage the additional carbon filter load.

### Do all carbon filters come with pre-filter wrap for the exterior of the canister?

Pre-filter wrap is not included with all carbon filters; thus, if you want a pre-filter included, be sure to check the product page specifics before purchasing.

### What’s the largest outer dimension of my carbon filter?

Increase the output size by approximately 2 inches. On a 4 inch carbon filter, the canister diameter would be approximately 6 inches in diameter.

### How long do carbon filters last?

Carbon filters are designed to endure for at least one year of continuous usage.

### Do I need inline and oscillating fans in my grow tent?

Inline and oscillating fans serve various functions in the grow tent, so it’s a good idea to use both if you have the option.

## What CFM Fan Do You Need For a Grow Room or Grow Tent?

The Common Culture inline duct fan is a tough, entry-level fan that is easy to maintain. It is intended to compete against more costly models because to its strong dependability and low noise levels, among other characteristics.

• 165 CFM with the ability to work with speed controls
• Mounts for the wall and ceiling are supplied. Color of stealth in matte black
• Warranty of five years
• Sizes of recommended grow rooms range from 2′ x 2′ to 4′ x 4′.

Vortex Powerfans are an industry standard, and are employed in locations where fan failure is not an option due to the nature of the work. Vortex fans are precision-engineered to deliver optimal performance at the lowest possible cost.

• 220 CFM having the ability to work with speed controls
• Heavy gauge steel shell that is impact-resistant and sound-absorbing
• Hammertone powder coat epoxy finish with a rustproof hammertone finish
• Warranty of ten years
• Sizes of recommended grow rooms range from 2′ x 2′ to 4′ x 4′.

Inline grow room fans with a diameter of 6 inches are the best. The Common Culture inline duct fan is a tough, entry-level fan that is easy to maintain. It is intended to compete against more costly models because to its strong dependability and low noise levels, among other characteristics.

• Inline grow room fans with 6 inch blades are the best. Inline duct fans by Common Culture are built to withstand the rigors of everyday use. Due to its great dependability and low noise levels, it is intended to compete against more costly brands on the market.

Developed using a Computational Fluid Dynamics (CFD) tool, the Max-Fan is the world’s first fan with this capability. CFD simulations are utilized in the design of aviation propulsion engines.

• 334 cubic feet per minute and compatible with speed controllers Fans that are 50 percent more efficient than equivalent fans The impeller’s 3D blades have been meticulously engineered to enhance efficiency. Warranty of ten years
• Sizes of grow rooms recommended range from 3′ x 3′ to 4′ x 8′.

Choosing the Best 8-Inch Inline Grow Room Fans The Common Culture inline duct fan is a tough, entry-level fan that is easy to maintain.

It is intended to compete against more costly models because to its strong dependability and low noise levels, among other characteristics.

• 720 CFM with the ability to work with speed controls
• Mounts for the wall and ceiling are supplied. Color of stealth in matte black
• Warranty of five years
• Sizes of grow rooms recommended range from 5′ x 5′ to 10′ x 10′.

A significant improvement in the durability of the Max-Fan Pro Series housing is due to the use of fiberglass reinforced plastic compounds that fulfill all of the UL and CSA criteria.

• 863 CFM, with a three-speed controller built in
• Fans that are 50 percent more efficient than equivalent fans Extremely low wattage to CFM ratio, which saves you money on electricity
• Warranty of five years
• Sizes of grow rooms recommended range from 5′ x 5′ to 10′ x 10′.

## Is having a duct fan important for grow rooms and grow tents?

Using a confined environment (e.g., a grow room, grow tent, etc.) to grow your plants will guarantee that they produce to their full potential. Proper ventilation will ensure that your plants produce to their full capacity. In a grow room, good ventilation is essential for maintaining humidity and temperature control. This is accomplished by expelling the heated air that is generated by your grow lights and electronic equipment. Cycling out this air also produces comparatively carbon-rich air for your plants to breathe more effectively, allowing them to produce more fruit and vegetables.

## What size duct fan and CFM do I need for my grow room?

There are several websites that provide a general rule-of-thumb for CFM calculation that does not take into consideration the differences between each growing environment. We’ll teach you how to calculate CFM by taking several variables of your growing environment into consideration, and then use that information to get the minimum CFM advised for your grow room. Volume of the Growing Environment: Determine the volume of your space by multiplying the length, breadth, and height of its dimensions.

Assuming there are no problems with heat, the growing environment volume in our case is 448 cu./ft., which implies we need to exhaust 448 cu.ft.

As a result, I’ve determined that I require a 224 CFM fan at the very least.

Take into consideration the following factors that may force you to have a higher CFM requirement for your grow room:

1. Lights: For each air-cooled light (600-1000w), double the result of the ‘Volume To CFM’ step by the equivalent of 10% of the result of the previous step. For non-air-cooled lighting, increase the amount by 20% per light. CO2: Increase the percentage by 10% if the room has CO2 enrichment provided by a CO2 burner or generator (which generates heat). Carbon Filters: If you’re using a carbon filter, increase the percentage by 20%. Increase the ambient temperature by 25% if you live in a hot environment (e.g., Southern California, Arizona, etc.). If you live in a humid and hot environment (such as Florida or Georgia), increase the percentage by 40%.

Let’s go over a complete example of computations that takes into consideration each of the four variables mentioned above one by one. Consider the 8′ x 8′ x 7′ grow chamber that was utilized in the previous example as a starting point. The airflow is now at 224 CFM, so that will be our starting point before we begin putting in the extras. For this example, let’s pretend the room includes two non-ventilated 700w LEDs, a CO2 burner, and a carbon filter, and we’re in Southern California. Lights: Increase the airflow by 20% each light multiplied by 224 CFM = 48 CFM.

The 96 CFM should be added to your computation of 224 CFM to get a total of 320 CFM.

This should be added to your 320 CFM to give you 354 CFM.

Adding this to our 354 CFM gives us a total of 402 CFM.

25 percent multiplied by 224 equals 56 CFM.

In this particular case, our final computation yields 458 CFM.

That being said, we would want to look for a fan with a greater CFM rating than 458 and we can always utilize a fan controller or fan speed controller to reduce the fan speed if necessary.

In this case, I would personally propose using an 8-inch fan that generates between 550 and 800 CFM and lowering the speed until the temperature and humidity are at their optimal levels.

## How long to keep a duct fan turned on in the grow room?

You should only leave your grow room’s duct fan running for as long as it is necessary to maintain the proper temperatures and humidity levels for your plants. As long as the temperature is between 65 and 85 degrees Fahrenheit and the relative humidity ranges between 40 and 60%, your plants should be content in their surroundings.

## How do you install a duct fan in a grow room or grow tent?

There are almost as many methods to install a grow room inline fan as there are ways to fry an egg, which is a lot of options. We’re going to include a few schematics of the most typical configurations for the inline fan and carbon filter in grow rooms further down this page. Inside the grow tent, there are four different ventilation configurations. Actual Photographs of a Fan, Carbon Filter, and Ducting Installation in a Grow Tent

## How do you clean to clean grow room exhaust fans?

First and foremost, make certain that your fan is unplugged. Then walk outdoors or put a sheet or newspaper down inside to catch any dirt or debris that has accumulated. Using a moist towel, clean the blades and interior of the exhaust fan to remove any remaining dust and debris. After that, you’ll want to take a can of compressed air and spray the interior of the fan in those hard-to-reach regions that you weren’t able to reach with a rag earlier in the process. Make certain that the fan has completely dried out before reinstalling it and turning it on again.

## Why have oscillating fans in the grow room?

Oscillating fans aid in the delivery of carbon dioxide to your plants, the even distribution of temperature and humidity within the grow environment, the increase in the robustness of the plants’ stalks and branches, and the reduction in the growth of mold and fungi on and around your plants as a result of their use.