how to grow marijuana in a hydroponic tent

Bud sites on a plant also need room to breathe. A little extra space encourages airflow between colas and helps prevent common diseases like powdery mildew and botrytis, and pests like spider mites.

If using a hydroponic system, the reservoir will likely be outside the tent, in which case, dedicated 2” irrigation ports will be needed to bring in water. The same goes for Blumline or drip systems.

When determining tent height, growers need to account for the type of light as well as space for an exhaust fan and carbon filter.

Electrical & irrigation ports.

AC Infinity’s CLOUD LAB 642. (Courtesy of AC Infinity)

In practice, this means operating multiple, self-contained chambers for vegetative and flowering plants because they require different amounts of light—18 hours of light per day for the vegetative cycle and 12 hours of light per day for flowering.

A tent’s dimensions are largely dictated by a grower’s choice in lighting. HID lights run hot and need to be hung high above plants, necessitating taller tents. Conversely, LEDs run cool, hang low, and play well in a short tent.

Flowering tents are taller and wider than those intended solely for growing plants in the vegetative phase. During the first two weeks of the flowering cycle, plants will double or even triple in size depending on the cultivar and environmental conditions. Growers give themselves as much wiggle room as possible for this phase, known as “the stretch.”

It does have a hefty price tag, but it’s a great kit if you don’t want to think about all the pieces involved in setting up a grow.

If your goal is to use just one structure to grow weed, you’ll need a tent that can accommodate plants at their biggest, which happens during the flowering cycle, or “bloom” photoperiod.

The CLOUDLAB Series also has a mounting plate installed on the front for their temp- and humidity-responsive fan controller (sold separately) for smarter ventilation.

Material density.

CLOUDLAB 743D. (Courtesy AC Infinity)

Matte black on the outside and shiny on the inside, grow tents are temporary structures designed for cannabis cultivation—offering a purpose-built place to hang lights and fans without permanently modifying a residential space.’s Dual Power Grow Kit ($995.95) is another great short tent to buy and comes complete with LED lights, fans and filters, a living-soil kit, timers, sensors, and hardware, and a 1680D-canvas tent that measures 5’ in height with a 2’ x 4’ footprint.

Weed plants are happiest when they’re in a temperature range of 20°F variance throughout day and night. When lights are off, temps should be no lower than 64°F during veg and 54°F during flower. When they’re on, temps shouldn’t be much higher than 84°F during either phase.

A sturdy piece of kit, the CLOUDLAB series boasts a best-in-class 2000D canvas shell, 150-pound weight capacity, and an all-steel frame complete with 22mm poles.


Before picking a tent, buyers should carefully consider where it will go and if that location is environmentally compatible and equipped with adequate utilities.

Other options include:

AC Infinity dominates our guide, closing with The CLOUDLAB 743D ($169.99), with a 4’ x 3’ x 6’ build, industry-leading 2000D canvas, an all-steel frame, and 150-pound weight capacity that I’ve grown to trust.

Tents come in sizes ranging just a few square feet all the way up to multi-room mini-mansions. Some are fairly basic and others are decked out in features that we’ll explore below.

Spare bedrooms usually fit the bill. Basements—cool in the summer and warm in the winter—are often well-insulated from daily weather extremes that can stress out plants. Untreated rooms are less ideal and should be avoided if possible.

For most cultivation setups, a room where a human would be comfortable in a t-shirt is perfect.

Dani Alchimia 2018-02-19 Hi JR Lautner, You should have no problem. I’d recommend you to use a 2-speed fan, so you can switch it in case you need more fresh air inside your grow (which usually happens in summer). Still, you can try with the fan you purchased, I think it’ll work properly. Best!

Matthew Mcneil 2018-09-15 Getting ready to order a tent and start growing. 4×4 And would like yo buy a complete set up. Light, balist, filter, fan all in one shot. Can you recommend any certain brand or how I should go about it?

In this article we’re going to explain some basics about indoor cannabis cultivation in grow tents, one of the most popular options among those who just want to grow some pot at home for their personal use. Being highly versatile thanks to the wide range of available dimensions, you only need to keep several factors in mind to successfully harvest your own buds.

Greg 2020-11-14 I have 2- 4×4’ tents and 1- 4×8’ led lighting in all with 2 fans in each tent. The 4×4 have 2 leds and the 4×8 has 4 leds. They have a switch for veg and bloom . Lights altogether cost 900.00 How many lights do I need in the tents? How should I use the veg/bloom switch? Do you use the veg and bloom at the same time and then switch to bloom as the plant matures? Or use each independently during each cycle of the plants life? Thank you.

Naomi 2016-08-02 Need help the leaves on the end of my plant have turned yellow and it’s not because their dry I have checked that just wondering what else coul it be and what can I do to help?

Growing marijuana with energy saving lamps.

leisa 2019-10-31 afternoon. how early can you start to add molasses to your babies.

Tim Alchimia 2020-08-10 Hi Wheatie, thanks for your question. Curing doesn’t really affect the potency unless the weed has been curing for a really long time, in which case much of the THC will have converted to CBN, resulting in a more heavy, stony and narcotic effect, but it won’t actually make it any stronger really. The main purpose of curing is to improve the flavour by allowing compounds such as chlorophyll, starches and sugars in the flowers to break down, making for a smoother smoke. The effect will also change slightly, from the up, speedy coffee high of freshly harvested weed, to a slightly more mellow and physical effect once the flowers are fully cured, depending on the variety. As a general rule, I find that Sativas and Sativa-dominant hybrids will benefit from a much longer cure of up to a year, while Indica-dominant varieties tend to only need a relatively short curing period and indeed begin to lose flavour quite quickly, sometimes after a few months. I hope that helps. Best wishes and happy growing!

I hope that helps, best wishes and happy growing!

Tim Alchimia 2020-11-16 Hi Greg, thanks for your comment and question. To calculate the lighting needed in each tent you need to now the output of the LED lights in lumens. The plants will need an absolute minimum of 2,500 lumens per square foot, although 5,000 is much better, up to a maximum of around 10,000 lumens per square foot during flowering, which is roughly equivalent to natural sunlight. The Veg/Bloom switch will change the lighting spectrum from a more white/blue light suitable for vegetative growth to a more orange/red spectrum that is ideal for flowering. I hope that helps you out, feel free to ask further questions and we’ll all we can to help. Best wishes and happy growing!

Papa Indica 2015-07-03 In my experience, a wing style reflector is the worst choice for tent growing, they seem to be better for more open spaces. Earlier on in my growing career I was using LED’s, near the end of that I had an HPS user friend of mine jealous of my results with them but, in the end, replacement costs were just outrageous compared to just replacing a bulb, or even a ballast. So, when I decided to switch over to HID lighting I bought a kit for my HPS set-up that included a wing reflector. I HATED that thing, the heat build-up in my tent was ridiculous, I had to dial my 600w ballast back to 50% power to try and keep it under control. By my second crop with HPS I had an enclosed reflector with my exhaust fan ducted to it to draw the heat out directly from the source. HUGE difference. I was able to bump back up to my full 600w and heat hasn’t been an issue ever since. But, also bear in mind that I’m using duct fans, not inline fans, so granted my fan may have just not been powerful enough to keep up the other way, though it seems to have plenty of pull to me. And by the way, I definitely get better results now with my HPS than I did with LED’s, I guess my friend is just a step behind. But anyway, to me, the enclosed reflector that you can duct your exhaust fan to is far superior to a wing for tent growing. (I have lots of opinions, don’t I?)

Tim Alchimia 2017-08-29 Hi, This is a relatively common problem in summer, indeed I know many growers that simply don’t grow indoors during summer to avoid just this problem! I’m not sure what the exterior temperatures are like where you are but one easy step you can take is to change the hours on your timer so the lights go on at night, when the exterior air is cooler, so the ambient temperature will be lower. Make sure your cool-tube ducting (insulated ducting will help lower temps too) is venting to the exterior well away from where you’re pulling the fresh air into the tent, and to make the extraction more efficient, make sure the ducting is as straight and direct as possible, without too many twists and turns which would reduce airflow and make the fans work too hard. Is the ballast for the lamp inside the tent? Can you move it outside? That would certainly help too. If these measures don’t make any difference, then you could look into cooling the tent with something as basic as a bucket of ice, or if that’s too simple, then maybe look into a portable air conditioning unit that you could direct into the tent. I hope that’s some help, happy growing!

Tim Alchimia 2021-04-08 Hi, thanks for your comment and question. I didn’t know that Subcool had made a Blueberry, they should be very interesting indeed! His genetics are definitely suitable for outdoor growing as well as indoor, although I think he did all his breeding indoors. I’d guess that, as with most breeders, there’ll be varieties that are more suited to outdoor cultivation than others, depending on mould and pest resistance, size and general structure. Search for a YouTube channel called Mendo Dope, those guys have done huge outdoor grows using Subcool genetics, with some spectacular results. I hope that helps, best wishes and happy growing! PS. I bet those Chem 91 cuts will thrive in your aeroponics set up indoors!

Indoor cannabis cultivation is easier thanks to grow tents.

Tim Alchimia 2020-08-04 Hi James, thanks for your comment and question. There’s no problem at all in leaving the door open while the lights are on, but you’ll need to make sure that the tent is sealed up again before the lights go out if you’re in the flowering period, otherwise you stand a good chance of stressing the plants and having hermaphrodite problems. I hope that helps. Best wishes and happy growing!

James Dean 2021-03-08 So I am curious on what some people are doing with whatever nutrient line they’re running.. My buddy that’s a good grower but does outside greenhouse said I should add molasses, mamoth, photosynthesis and a veg Enhancer. Just wanted to see what your opinion is.

Related Posts.

Ryan S C 2018-07-19 Hi everyone i have just set my 120/80/160 tent up with 600w led and 5inch extractor fan an carbon filter how many plants would you recommend i could do in that it’s my first time growing.

Dani Alchimia 2017-04-03 Hi terry222, Excellent question! Outdoor plants are used to a changing environment, they have sunny days, rainy days, cloudy days, and different moon phases. They adapt to these conditions and react accordingly. On the other hand, indoor plants have much more constant environmental conditions. It must be said that they can also tolerate a certain amount of light during the night period and bloom normally, but it is always better to avoid light sources since indoor plants are more sensitive to environment changes. That’s why complete darkness is always recommended, so you don’t take any risk of stressing the plants. Hope it helped!

Nick 2021-06-17 Hi Tim! New grower here. I live in a hot and humid place that has no seasons, we do get rain and dry seasons . I was wondering about using a grow tent but Im not sure if it will be hard to keep a low temperature with such an enclosed environment specially in hot and dry seasons. How do you feel about using grow tents in this kind of environments?

Dani Alchimia 2016-08-17 Hi Naomi, If you mean the lower leaves of the plant, then you need to add more nitrogen to your nutrient solution. Using any fertilizer formulated for the growth stage should solve the problem. On the other hand, if you mean the upper leaves it could be caused by the heat emitted by the bulb. Placing it a bit further from the plants should lower the temperature of their tops and allow plants to grow normally. Hope it helped! 😉

Tim Alchimia 2021-05-20.

wheatie 2020-08-10 hey tim for marijuana to be potent is it correct to let it cure forhowlong for sone strong potent marijuana thanks.

Plants must be watered according to their needs.

Lighting System.

Justin 2020-02-05 Kids have a 48×48×80 I have a 1200 w led light it equals 600w is that big enough.

JR Lautner 2018-02-18 I am starting a 2x4x60inch grow tent. I have a four inch carbon filter kit and 2 600watt leds 277 true watts each. This will be in my michigan basement die to the moist cold air in the basement I am going to draw the intake air from a room on the main level. I will be moving the air about 12 ft with a big drop to the bottom of the tent. I purchased a 4 inch In line duct booster fan will this work for me.

Dani Alchimia 2016-10-06 Hi Levi, As you say, light is not so important during the first stages of the plant, but it is imperative to get good yields once into flowering. Grow tents have been designed to keep a good environment for the plants while protecting them from light sources during their night periods. Thus, they’re very convenient but not strictly necessary, especially in regard with yields. What you do need is a good light source (the Apollo 400W would be ok) and proper air renovation in the growing space (and of course controlling the temperature and humidity). These basic tips for indoor gardening should be useful for you. Hope it helped!

Relative humidity should not exceed 75% (maximum) and should’t be lower than 20% (minimum). The ideal humidity is between 40 and 60%. Sometimes it can exceed 90%, what shouldn’t be a problem if it happens only in particular occasions. A thermo-hygrometer is necessary to control these parameters in our growing space.

Tim Alchimia 2018-03-13 Hi, thanks for the question. Ideally you’ll vent from the top of the tent to evacuate any hot air, but it can work fine either way. Venting the air up a tall chimney sounds like a great idea, but I’d still recommend using a carbon filter to avoid the smell being spread over a wide area! All the best and happy growing!

Tim Alchimia 2019-11-01 Hi Leisa, thanks for your question. If you want you can give your plants molasses in low doses from a very early stage, once a few sets of leaves have developed. It won’t act as plant food as such, but it will help to feed the beneficial microbes which in turn will improve nutrient uptake and efficiency in your plants. You can add molasses (making sure it’s the un-sulphured type) throughout growth, increasing the dosage as the plant develops, but it’s during the flowering phase when it will be most beneficial. All the best and happy growing!

Hashmagus 2021-02-09 Hey guys I am a new grower & was wondering if I use 250watt M/h and 315cmh with 4k bulb. Will I get better results. Than just using hps.

Sid Strandberg 2017-10-03 Im thinking of having perhaps 4 plants in a tent ( making them pretty big) how much Watt do i need on my LED for best grow? Im thinking about roleadro 300W but is it to low for 4 plants i found another one that has 1000W ( all the watt is measured on LED basis) Or does it depends on the size of tent? what size for A good tent for 4 plants, 300w/1000W LED? And regarding the seeds, i have grow Bubblegum before, but i guess now when im doing indoor i should be doing Indica because they will fit better in the tent? or you have sativia strains that does not get to height in lenght? feel free to suggest some strains. I would also need nutrients, soil and all of it hehe.. Thank you for the help!

$60) – I love the CoolGrows branded tents. I’ve tried them in a few different sizes and they are generally higher quality (better zippers, more sturdy) and yet cost less than other “generic” tents. I just wish they offered the 2’x4’x6′ size.

You want to make sure no light or smells will make it outside the tent!

It can be tempting to try to get a really expensive grow tent with all the “bells and whistles” because you want to give your plants the best possible home! But honestly the cheapest grow tent has 90% of the features of a far more expensive grow tent. If you’ve never grown marijuana before and are reluctant to invest a lot of money, I recommend starting cheap when it comes to tents!

When used correctly, a grow tent lets you recreate nature under its most ideal conditions! Possibly the hardest part of being able to grow cannabis in these ideal conditions is getting set up. However, once everything is set up, it’s mainly a matter of planting a seed and watering your plants until you harvest bud!

Grow Light Compatibility.

$85) – Another CoolGrows tent. This size tent can support even the biggest HID grow light, the 1000W HPS. I personally think it’s the perfect size for a 600W (the most efficient of all grow lights, and it can produce more than a pound), so you get the best and biggest results as possible without dealing with a ridiculous amount of heat or killing your electricity bill.

It’s important that there is an air-tight line from the carbon filter to the fan (without any air leaks) in order to prevent smells from escaping the tent!

Short plants can only yield so much even if they’re completely covered in bud.

If you want to double your yield from a 2’x4′ but don’t want to have to set up a whole grow room, a 4’x4′ is the way to go! It’s big enough for monster yields (a pound or more!) but still small enough to be manageable by just one person.

If you have a smell emergency, you can use an exhaust fan directly attached to a carbon filter sitting on the floor. This isn’t as effective as a “real” exhaust system, but it will clear an entire room of smells in just minutes. Some growers who can’t fit a carbon filter in their grow space have even used this technique to control smells for a whole grow!

Examples & What to Look For.

What Size Grow Tent?

Grow tents are designed to keep things simple for hobbyist cannabis growers. As convenient as grow tents are, they’re not designed for huge marijuana grow operations! But for someone who wants 1-5 ounces/month, a grow tent may be the best way to go!

Get Started Growing! You Are Ready!

To get better airflow without light leaks, you can make a little “window” or light trap facing down (using the built-in intake vents) to let air through, but not light.

Cheap rope ratchets allow you to move a grow light up and down with a few clicks, so you never need to hold up your light or worry you might drop your light on your plants.

For bigger growers, a 4’x4′ grow tent is great because it can be used with the next class of grow lights up to some of the biggest grow lights. It can support a 600-1000W HPS or LED grow light as long as it’s 6-7′ tall.

Example of a cannabis plant in a grow tent.

Note: When you open the door of the tent it breaks this seal, which means smells may flood out the door or get pulled into the exhaust fan prematurely. To deal with smells when you open the tent, you can use a product called ONA gel, which is surprisingly effective at covering up odors on a short-term basis .

4.) Connect Carbon Filter – No Smells!

I think the best way to make an efficient exhaust system is to hang your exhaust fan inside the tent. This significantly muffles the sound of the fan running, and lets you create a relatively straight path from your light to the fan for maximum circulation and airflow.