How To Cool A Grow Tent: Cheap And Affordable Ways

I know you’ve probably spent so much on the grow tent. And you can’t take it anymore. The last thing you want is to incur some more costs on your grow tent.

Everything with the grow tent works, except for the high temperatures, which have started affecting your plants. The water in the soil is evaporating so quick, and the plants are wilting.

You might think you’re alone in this. Well, you’ll be surprised how many indoor gardeners are having the same issue. It’s not that you’re a novice or something, you just gotta make a few tweaks to your grow tent and everything will be okay.

Now, maybe you’ve already tried a few things here and there, but nothing seems to work. Don’t fret though, coz I’ll be showing you what you need to do. Most of these remedies on how to cool a grow tent are simple and you won’t have to dig deep into your pockets.

So, let’s dive in

What Really Happens When Your Grow Room Records High Temperatures?

For starters, it’s obvious that you’ll never have the high yield you’re expecting. That’s the reality. But from a technical point of view, when temperatures are high, it means that your plants are “sweating” profusely.

And, just like human beings, plants cannot survive in temperatures that are higher than their optimum requirements.

In other words, temperatures for plants is all about roots and leaves, which are affected by humidity, air movement, and intensity of the grow lights. Plants usually cool themselves through tiny holes in their leaves called stomata. Here, the warm water vaporizes, which then cools the plant.

However, if the temperature is too high, the stomata become dried up and thus causing stress on both the leaves and the roots. Thereby, no photosynthesis can take place. This shuts your plant down whereby flowers don’t form properly, fruits ripen prematurely, and plants grow tall and leggy. Basically, it’s a major bummer 😥😞😔

Therefore, if you didn’t know, now you know. And you gotta find a solution ASAP.

How Warm Should My Grow Room Be?

It all depends on the type of plant you’re growing, some of which do well in higher temperatures than others. Still, it’s advisable to keep your temperature between 68 and 75 Fahrenheit.

The objective is to try and replicate temperatures that naturally enable the growth of the plant you’re gardening. For instance, during the day, make sure your thermometer reads a level that doesn’t go beyond 80 Fahrenheit. At night, the temperature has to be a little bit cooler, in replication to the natural requirements. Therefore, keep the temperature at an average of 73 F.

Such a balance between day and night temperatures is exactly what is needed for the plant. But if things seem a little bit off what I’ve just mentioned, then it’s best you cool your indoor grow tent with remedies such as ice, or an affordable inline grow tent fan like the VIVOSUN Duct Fan, which goes for just $18.49

A fan inside the grow tent protects the plants from dying out. A great tip is to make good use of a 650cfm fan that’s oscillating air through the grow tent carbon filter. And if you can afford it, you can install an HEPA verified AC. Now, let’s have a look at some of the things and tips you can do to cool your grow tent.

(1) Using Inline, Exhaust and Clip-On Fans

I think it’s a rule of thumb to use some sort of fan in cooling your grow tent. I’ve never seen a tent without a fan. But, which fan should you use? Should it be the oscillating type? Or the inline fan?

There are different types and you need to know which one is perfect for your specific grow tent. From experience, the inline and exhaust fans have proven to be the most effective. Both types of fans are almost similar in their functionality. They are kinda two peas in a pod, but with minor differences.

That is, both inline and exhaust fans work by making sure the heated air within the grow tent is pushed out whilst bringing in fresh and unheated air. The best thing about this is a guaranteed air flow in and out of the grow tent. It keeps hot air outside the tent, thus a cooling effect.

The only difference between the inline and exhaust fans is that the former is more compact and been designed to easily connect with a carbon filter. However, even the exhaust fan is possibly connectable to the filters. Basically, with a balanced set of the two fans, you should expect positive results, with highly minimized temperature of the grow tent.

In addition to the inline and exhaust fans, you can also opt for the clip-on fan, which is not only very lightweight but also easy to install. What I love about the clip-on fans is that your grow tent will be getting a constant flow of air, as well as guaranteeing steady breeze of wind, which is critical to the plants.

This makes the plants feel like they are in their natural habitat, because of the breezy wind.

Although it costs a few bucks, the clip-on fan adds some serious value to the grow tent. Which helps keep off insects and pests. I’d suggest getting the Comfort Zone CZ6C, which is a simple clip-on fan.

Noteworthy Tips Regarding the Fans

Be careful and buy additional ducting such that you point out the fan’s ducting to a nearby window. This way, none of the air coming out of the grow tent isn’t mixed up with air from the room you’ve installed the tent.

That is, if don’t extend the ducting to an outside window, the same heated up air will keep coming back into the grow tent. And you wouldn’t want that, would you? So, try and make sure none of the air sucked into the grow tent isn’t compromised at all.

(2) Cooling Grow Room with Ice

Since we are talking about cheap ways to cool down your grow tent/ grow room, then using ice cubes is a really great idea. Believe it or not, but this method can actually keep your tent’s temperature at around 70 – 74F. If done well, it doesn’t disappoint.

All you have to do is freeze a gallon of water (depending on your tent’s size), place it in your grow tent, and situate your fan to blow it. Actually, it’s pretty simple and doesn’t require much expertise. The only biggy here is that the process isn’t a universal procedure for every tents.

Normally, grow tents tend to be of small sizes (2×2’, 4×4’, and even 5×5’), which may seem too small for a gallon of ice. Unless you’ve got a large grow tent, I recommend that you to go with a smaller ice box, perhaps a single ice chest.

For those with larger grow rooms, they’ll probably need an air conditioner. But hey, we’re trying to find alternatives on how to cool a grow tent without an AC.  The ice box is already playing an amazing and useful alternate.

Now, you need to know that there are two types of ice you can use for this purpose – the Dry ice and the normal ice. We don’t have to dwell on the normal ice 👌✌ whereby a gallon of it can last up to 3 hours. But then again, it’s all about your tent’s size, so try out different amounts of ice.

On the other hand, the dry ice is made of CO2 and doesn’t melt as fast as the usual ice. When you place a fan to blow through it, then the dry ice evaporates into CO2, which helps plants to breath.

With dry ice, you get to kill two birds with one stone. You not only get to cool your grow tent, but you’re also helping feed the plants with enough oxygen. The only downside is that you’ll have to incur a few extra bucks to get dry ice, but you can with the LIVE 2DAY Dry Ice Packs. It’s worth it.

How to DIY an Ice Box

  • You’ll need an ice chest, one with styrofoam on the sides. You can also use a polystyrene container. Here, you’ll have the water for freezing into ice. And if you’re using the dry ice pellets, the here’s when you use it.
  • The next thing you’ll need is a small fan. You can use an electrical one, or a battery-run alternative. Just make sure it’s sizeable enough to install right next to the frozen ice.
  • The third step is to get a duct hose, whose size and length will depend on your tent’s size. Just make sure to set up the duct to be as liner as possible.

(3) Relocate Your Grow Tent

You need to reconsider your grow tent’s location. It might be problem and the reason why your tent’s temperature doesn’t cool down easy. If you’ve got a section in your house that’s near the window, it’s better you relocate the grow tent there. You can also relocate it to your basement, if that’s where the room temperature is cooler. Just move the tent somewhere less heated up.

But, it doesn’t mean that moving your grow tent somewhere away from where it already is will guarantee a lower temperature. Remember to consider how you’ll be aerating the air from the fans.

I mean, you might relocate it to the basement, which is the colder room of your house, but then it might not have a window where you can extent the ducting with the outside world.

Also, if you’re using hydroponics, then make sure the equipment stays outside the grow tent. Such may include the likes of pumps, chillers, filtrations, etc., some of which may contribute to increasing temperature within the tent.

(4) Using Lighting to Cool Down Your Grow Tent

Now, you gotta be cautious of the type of lighting you use. If you get it wrong, then you risk killing off your plants due to high temperatures and humidity. It’s self-evident and crystal clear that you gotta reduce temperature at night; thereby, low wattage lighting bulbs are needed.

The best tip is to use water-cooled lighting systems. With the water-cooled best LED grow lights, your grow tent will be experiencing a more natural lighting. That is, such water-cooling LEDs have small shadow footprint on the tent, whereby it allows for more sunlight to penetrate into the grow tent.

Water is great when it comes to efficiently transferring heat from the LED lighting to where it’s cooled off and then reused for heating. The lighting system guarantees a controlled temperature.

I’d also advise you to make sure your tent’s lighting have proper fans. That is, when you’re buying lighting bulbs for your grow tent, make sure to recheck if the bulbs come with some sort of a cooling mechanism. In essence, a lighting system that features a cooling effect is what you need. It is what everyone needs.

(5) Make Sure You’ve Got the Right Air Circulation Setup

You need to understand that when the grow tent has a normal and constant air circulation, the likelihood of experiencing heated air within the tent are minimal. Therefore, you need to control this circulation. And do you do that?

It’s actually very simple. You just need to remove the warm air via the tent’s top section, and then replace it with colder air from the bottom section. That is, the warm air is always lighter than the cold air, thereby the heated air is always rising to the top section, which is then to be removed.

Here’s where you use one of the best inline fans for a grow tent, which sucks the heated air out of the grow tent and then directing it to the outside world, out of the room – get a really long ducting system for that. Now, there are two ways to set up air circulation. The first is the aforementioned, whereby you just install the inline fan at the top, as the tent’s bottom port lets air into the tent, automatically.

The second method is similar to the first one, whereby the inline fan sucks air outside from the top of the tent. But then again, you’ll have to install another inline fan at the bottom of the tent, to help with further sucking of air into the grow tent.

The first method, without an inline fan at the bottom is referred to as the passive air circulation system for the grow tent. As for the second method, it’s known as the active system.The second method (the active system) is preferable because the grow tent gets to have constant air flow into it. However, you’ll have to spend more on the extra inline fan. But hey, if it’s worth it, then it’s best you get one.

If you can’t afford an additional inline fan, then I’d suggest you increase the space at the bottom of the tent, which is gonna let in more air. The plan is to make sure that the top outlet and the bottom inlet are of the same size in terms of sucking out warm air and letting in cold air. There shouldn’t be an imbalance.

(6) Finding the Right Sizing for Your Ventilation System

Similar to air circulation, ventilation setups are vital in guaranteeing a cooled down grow tent. Once you’ve got an effective ventilation system, you won’t have to worry about your plants dying off. Neither will you have to worry about bad odor coming from the grow tent.

It’s recommendable that you replace the air on intervals of 5 minutes. The spaced-out intervals should be less than 5 minutes if you’re experiencing overheating of the grow tent. Therefore, it’s important to find the right sizing of the ventilation system.

For starters, you need to have better estimates of your fans’ CFM, which is the cubic feet per meter that measures velocity of air flowing in and out of the grow tent. You need a perfect balance of air getting in and out of the tent. Hence, in calculating the CFM, the formula is:

Grow Tent’s (Width X Length X Height) /5 = CFM

You’ll need to find a fan with the appropriate CFM that’s gonna be suitable for your grow tent. It’s worth noting that CFM calculations and performance are usually affected by both the length and the path of ducting. The CFM is further affected by a carbon filter – such as the iPower Carbon Filter.

Just remember to add the aspect of a carbon filter to the CFM calculation. Thereby, the formula now becomes:

[Grow Tent’s (Width X Length X Height) /5] X 1.2 = CFM

(7) Switching from HID to LED Grow Lights

When choosing the right lighting bulbs for your grow, you don’t wanna cut corners. It’s important that you get the right grow lights.

Basically, the HID grow lights are usually hotter than the LED grow light, which means you gotta switch to the latter. The LEDs grow lights are usually effective in cooling your grow tent. Although they are a little bit costlier, it’s worth getting them.

Some of the benefits why you should switch to LED include the following:

  • It’s an eco-friendly lighting system, which doesn’t use toxic metals
  • The LED lights can stay lit for more hours
  • LEDs save energy by 60 to 70 percent of the range
  • There’s no cooling needed coz it’s already cool and cold
  • Most of the LED lighting requires no reflectors
  • LEDs boast of flower production and maximum absorption of chlorophyll

When it comes to indoor gardening, lighting is very crucial and definitely a big deal. That is, the LEDs are one directional and they are known to deliver light uniformly across the plants.

If you’ve decided to make the switch from HPS grow lights to LEDs, then don’t forget to buy the likes of Mars Hydro TS-3000, which has the advantage of having removable drivers. Which helps with cooling off the grow tent.

(8) Better Insulation and Run Operations at Night

I guess you already know that your grow tent must have an air-tight insulation. But that’s like to preaching to the choir, coz you probably must have confirmed that already.

Still, such insulations usually go both ways. For instance, if you are in a state like Maine, whereby the weather is always cold, then the insulation will be very helpful. But if you live in warmer states like Florida, then you’ll need to find alternative ways providing air circulation at all times.

You can guarantee this by use of an air conditioner. Nonetheless, you’re perhaps broke and don’t have money to get an air conditioner. In such a case, you can always find other ways on how to cool a grow tent without AC. For example, you can decide to use ice to reduce temperature in the grow tent.

For those in cold regions, you can always leave your lighting bulbs on the entire night. This way, the grow tent is warmed up, thus protecting your plants from forming buds and dying off the leaves.

As for The Final Thoughts…

When it comes to ways on how to keep temperature down in a grow tent, there are innumerable methods. And as you can see, there isn’t one particular and best solution.

Depending on the type of plants you’re gardening, as well as relying on type pf grow tent you are using, you can never pin-point the exact reason for a heated up grow tent. That’s why I have illustrated eight (8) different methods you can use to control temperature in your grow tent.

It’s actually an art trying to lower your tent’s temperature. And that’s why it’s advisable to try all the methods one after another until you’ve found one that’s effective.

Most of the aforementioned ways of cooling your grow room are affordable and you don’t have to spend so much on buying new gadgets. However, you’re gonna have to cough some money on certain items, such as the inline fans.

Nonetheless, good luck cooling off your tent.

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