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Image by Felipe Vieira
Writer's pictureJim Jones

How to Set Up and Maintain a Cannabis NFT Grow System

Updated: Oct 17

There are many different ways to set up an NFT system, from the basic plug-and-play complete kits to the more complex drain pipe and net pot models.

In this article, I break down all you need to know about how to set up and maintain your NFT system, providing a step-by-step tutorial on setting up a basic beginner’s kit as well as the DIY version for the more adventurous. Without further ado, let us delve deep into the highly rewarding world of nutrient film technique and discover how easy it is to use these systems and why they are the ultimate entry-level hydro system for a beginner grower.


  1. The different types of NFT (Nutrient Film Tcechnique) systems available

  2. Complete, ready-to-go NFT kits for growing cannabis

  3. The pros of a complete NFT kit

  4. The cons of a complete NFT kit

  5. Which type of water pump do I need for NFT?

  6. What is a spreader root mat, and how does it work?

  7. How to set up an NFT kit grow for cannabis

  8. The D.I.Y NFT system option for growing cannabis

  9. The pros of building your own drain pipe NFT setup

  10. The cons of building your own drain pipe NFT setup

  11. How to build a DIY NFT system using plastic pipe

  12. Requirements

  13. Step 1

  14. Step 2

  15. Step 3

  16. Step 4

  17. Step 5

  18. Step 6

  19. Step 7

  20. Step 8

  21. Step 9

  22. Step 10

  23. Which pipe angle is best for homemade systems?

  24. How to maintain and care for your plants using an NFT setup

  25. Reservoir changes

  26. Nutrient solution

  27. Water temperature

  28. Controlling pH and E.C

  29. My 3 top tips for maintaining your NFT system

  30. My final thoughts


The different types of NFT (Nutrient Film Tcechnique) systems available

A nutrient film technique (NFT) hydroponic system requires only a mild stream of nutrient solution for plants to grow. As the plant roots are in permanent contact with the film of water, the versatility of these systems extends to various system designs, shapes, sizes, and requirements. Below, I explain the two types of systems a beginner grower may encounter.


Complete, ready-to-go NFT kits for growing cannabis

For those fed up with a dirty, low-producing grow room and constantly sweeping up soil, then fear not…a complete NFT kit is only a click away! Many brands offer NFT tank/table designs, ranging from small systems designed for 1–2 plants to larger designs that can house up to 16 in a Sea of Green setup.

These types of systems use 4 or 6-inch rockwool cubes and are capable of enormous yields and a prolific root mass. You can expect to pay anywhere from $75-$500 for a complete kit, with a set-up time of around 30 minutes for the cheaper versions.


The pros of a complete NFT kit

  1. You cannot go wrong as a first-time grower with a complete kit.

  2. The assembly time is minimal compared to building one from scratch.

  3. You can grow 1-2 heavy-yielding plants in a stealth grow box using the smallest NFT kits available.

  4. Complete kits contain everything you need and everything you’ll need to adjust the pH levels of your nutrient film nutrient solution (pH up and down).

  5. These systems are available in different sizes and dimensions.

  6. Short NFT-designed systems provide more growing space indoors.

  7. Reservoir changes are straightforward and take 20 minutes.


The cons of a complete NFT kit

  1. Most systems will not exceed more than 180 cm in length.

  2. You should purchase a backup pump.

  3. Stealth grow box and tent growers may be limited in model size.

  4. Large-sized systems can become expensive, costing $1000+

Two examples of NFT options

Which type of water pump do I need for NFT?

Your journey to becoming a full-time NFT grower is simply plugging in a water pump, but which type of pump will you need for an NFT (Nutrient Film Technique) system? The trick is to provide an optimal flow rate, allowing the water to create a fine water and nutrient film that pours down the top tray or drain pipe.


You only need to use a small-sized pump capable of producing a steady stream of nutrient solution. A spreader root mat will then absorb the water and distribute an even amount to the roots. Once your system is set up and working, you will notice a pleasant dripping sound created by the run-off.


What is a spreader root mat, and how does it work?

The spreader root mat is made from finely layered fiber strands and has an excellent ability to retain water. Once placed down over the top tray, the mat’s role is to act as a bed for the plant’s root systems to grow onto through the bottom and sides of the 4-inch rockwool cubes.

NFT Mat usage for marijuana grows

An example of how a spreader mat for NFT can be used

How to set up an NFT kit grow for cannabis

Out of all the hydroponic systems, I find the complete nutrient film technique system the easiest to set up. If you are working with the black plastic box design complete kit and not the drain pipe version, you only need to place the water pump at the bottom of the tank and connect the fitting to the top part of the tray.


Once that is in place, lay the provided root mat on the top table, then decide how many plants you will grow in the 4 or 6-inch rockwool cubes. It is important to keep the top tray covered from light to prevent algae development, so carefully cut out the template you require based on the number of plants.

If you are working with a 140 cm x 50 cm table, I would suggest planting 4 to 8 plants depending on the cultivar (strain); however, more than this may cause overcrowding during flowering. Below is a short list of what you can expect when ordering a complete NFT system.

  1. 1 x 60 liter tank

  2. 1 x NFT top-tray

  3. 1 x corriboard top-plate

  4. 1 x MJ450 water pump

  5. 1 x pump fittings

  6. 1 x spreader root mat

  7. 1 x PH up and down

  8. 1 x PH test kit


The skilled people from Greens Horticulture have an amazing video about an easy NFT system set up. Take a look at the video above!

The D.I.Y NFT system option for growing cannabis

Cannabis NFT drain pipe

A 3D render of a NFT drainpipe system

Many different DIY NFT setup ideas are floating around on the web, from an abundance of custom-built drain pipes to zigzag designs to vertical grow systems. If you look them up, most of these results will provide pictures of lettuce, which can leave you wondering what the NFT hype is about.


Building your system and using a drain pipe can be an excellent way to create a recirculating hydroponic system custom-built for your indoor or outdoor growing space. Assembling the drain pipe together and creating the right angle to produce the adequate flow rate is easy enough to do and will be covered later in this article.


The pros of building your own drain pipe NFT setup

  1. Drain pipe style systems are better equipped for smaller-sized plants.

  2. They can be set up outdoors on a large scale, leading to plentiful yields.

  3. There is no need to hand-carry water, making these systems ideal for those short on free time.

  4. You can customize the number of plants you harvest each time.

  5. Vertical farming used on a commercial scale proves the effectiveness of NFT.


The cons of building your own drain pipe NFT setup

  1. Basic plumbing, drilling, and assembly are required, which may deter some.

  2. Sourcing all your materials at once may be difficult and require several trips.

  3. The roots of a plant, grown in a pipe design, will yield significantly less than rockwool.

  4. Some materials may not be lightproof, promoting the development of algae.

  5. Once set up, you may be reduced to the amount of vertical growing space indoors.

  6. The net pot and hydroton method will produce smaller yields compared to rockwool.

Cannabis hydro grow

A net pot with a marijuana plant for hydro growing

How to build a DIY NFT system using plastic pipe

Building your own homemade NFT system can be highly rewarding on many levels. What I love most about designing your own model is the simplicity. You only need a plastic drain pipe, a plastic tub to house the nutrient solution, and a small fish tank pump and plastic tubing. This example below is based on a tub and plastic pipe measuring 90 cm long, designed for three medium-sized cannabis plants in rockwool cubes.


Requirements

  1. 1 x aquarium fish tank pump

  2. 1 x 10-14 mm plastic tubing

  3. 1 x plastic tub and lid (90 cm long)

  4. 1 x 6-inch plastic water pipe (90 cm long)

  5. 2 x 6-inch pipe covers

  6. 3 x 4-inch rockwool cubes

Step 1

Remove the lid of the plastic tub (that will serve as your water reservoir) and place the fish tank pump firmly at the bottom of the tub on one side. Then attach the 10-14 mm tubing to the pump and cover with the lid. 

Step 2

Drill a 10mm hole in the top of the lid on the opposite side of where the pump is located. This is to feed the tubing from the pump into the pipe above.

Step 3

Drill a second 25mm hole in the top of the lid on the opposite side of the first hole (step 2). This hole is where the water will drain through before recirculating back.

Step 4

Mark on the 90 cm water pipe where you will insert the rockwool cubes. Every 30 cm, make a clear marking. 

Step 5

Now cut out an area 4 inches square in size where you have made the markings. This is where the 4 inch rockwool cubes will slot inside and downwards. 

Step 6

Using a drill, make a 10 mm hole in the lowest part of the pipe covers, acting as an entry point for the pump hose to enter and for the water to drain out. 

Step 7

Once you have inserted the 4-inch rockwool cubes inside the pipe, and the covers are on both ends with the water pump hose attached on one side, you are now ready to mount the pipe.

Step 8

Mount the pipe in the center and across the tub. Fix the pipe to the top of the tub using adhesive plastic glue. The easiest way to angle the pipe is to place a small piece of wood under the side where the water enters. 

Step 9

Once the pipe is firmly attached to the tub and lid, insert the water pump tube into the hole made previously in step 6. (You’ll only need to remove the lid and drain the water out during reservoir changes).

Step 10

Fill the reservoir with water and test the system’s dynamics. Ensure a mild flow of water is passing through and lightly dripping. If you need to adjust the angle of the pipe, use a smaller piece of wood to raise the pipe as close to 20 degrees as possible.

Which pipe angle is best for homemade systems?

You will want to angle your drain pipe channels at an angle as close to 15–20 degrees as possible. Avoid any angle higher than 35 degrees, as this may cause too much indifference in the final plant height when building large systems. You certainly don’t want the piping to be horizontal or too steep.

setup angle for NFT

The angle for a NFT setup

How to maintain and care for your plants using an NFT setup

From my experience using nutrient film technique, these easy-to-use and low-maintenance systems basically run themselves. Once the plants are in place and the water temperature is set to run at 64.4 degrees Fahrenheit (18 ℃) consistently, there is little upkeep needed to ensure healthy plant growth.


Reservoir changes

A change of reservoir simply means removing the old nutrients and replacing them with a freshly made solution. You’ll need to change it every 5–7 days. To do so, connect your hose pipe fitting to the pump and let the reservoir drain.

  1. This simple process should take around 15–30 minutes in total.

  2. The hose fitting comes as part of the kit, so there is no need for you to chop a garden hose.

Nutrient solution

You will only be able to use hydroponic nutrients with NFT systems, so getting into the habit of mixing your nutrients according to the exact amount is key. If you are unsure about the right amount of nutrient to use, follow the feeding guide chart provided by the nutrient brand. When operating large systems capable of holding 120 liters of water, be prepared to invest heavily in the nutrient front.

  1. Once you have made the nutrient solution, stir well and let it sit for 5 minutes.

  2. Always check the pH after you have added the nutrients to the water.

Water temperature

One of the unfortunate things about the NFT kits is that they do not come with an aquarium tank heater. Ensuring the water temperature is in the perfect range for the roots requires a good-quality water heater. Buy these at an aquarium store; it will set you back around $30.

  1. Avoid cold water temperatures, which can cause plants to become wilted.

  2. Do not allow your reservoir to exceed 77 degrees Fahrenheit (25 ℃).

Water heater

Aquarium water heater from Walmart

Controlling pH and E.C

The pH and E.C. of your nutrient solution will play a massive role in nutrient accessibility and the plants’ ability to fully utilize the available micro and macro minerals in the water. Using pH up or down will allow you to check if the pH level is optimal. The E.C. of your nutrients will increase over time depending on the cultivar (strain) and your plants’ maturity.

  1. Keep a digital pen close by for checking pH and E.C. levels.

  2. Start your plants off on a low E.C. and gradually increase over time.

Bloom city ph

pH up and down bottles from Bloom City

My 3 top tips for maintaining your NFT system

Top tip #1 – I love using 10% hydrogen peroxide or “food-safe” bleach solution after every harvest. It ensures my tank is as clean as possible and pathogen-free. Give your tank, top tray, and pump a deep clean after every crop.

Top tip #2 – Check on the state of your roots as often as you can. It is important to produce healthy, bright white roots with a noodle and fish bone consistency. Roots displaying a brown or yellow color can indicate root rot.

(un)healthy marijuana roots

Examples of healthy and unhealthy roots in hydro setups

Top tip #3 – Turbine wave makers are a cheap and effective way to produce a consistent water current in your reservoir. Place one at the end of your tank, as this will create more oxygen and make little noise when operating.

Wave maker

Wave maker from Walmart

My final thoughts

At one point or another, every grower becomes fed up with the mess associated with organic growing. The thought of working indoors with a soilless, easy-to-set-up, clean, low-maintenance, and massive-yielding system can be a breath of fresh air that rejuvenates any grower.


Be prepared for a bed of roots so colossal that even the water pump will become engulfed! You have to see it to believe it, which is why I am one of the best advocates for promoting these highly rewarding hydroponic systems.

The best advice I can give a beginner grower stepping into the world of hydroponics is to be prepared to expand your knowledge and learn as much as possible about the subject. One of the best ways to do so is to roll a joint, get comfy, and check out Robert Bergman’s Grow Bible.


I cannot stress enough the importance of creating a sterile environment by keeping your NFT system clean during the entire grow cycle. Using hydrogen peroxide and bleach is the best way to guarantee a deep clean. If in doubt…get the bleach and peroxide out! As always, make sure you have backup water pumps. Good luck mastering the art of nutrient film technique and knocking your yields out of the park!

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