Nutrient Film Technique in Aquaponics

October 06, 2021

As you may know, the Nutrient Film Technique is one of the many grow methods available in an Aquaponics system. The NFT is a simple, yet fascinating method that works great for farmers who are looking to grow lettuce, baby herbs and strawberries.

What is the Nutrient Film Technique?

This technique was originally adapted from Hydroponics as the setup is pretty simple and easy to use. The system is composed of horizontal pipes or water trays where the plants are suspended in net pots. Then a steady stream of water is pumped through the pipes/trays, providing the plant roots with nutrient-rich water. Unlike the Flood and Drain Media beds, the Nutrient Film Technique does not require a draining method as the water is continuously circulated through the system.

Due to the lack of available surface area for bacterial growth in a PVC pipe, it is important to ensure that your mechanical and biological filtration is up to scratch. Your biofilter houses your bacteria that carry out the important steps of the Nitrogen cycle. Therefore, in an NFT system, you need to ensure that your biofilter houses enough bacteria to support your entire system.

Lettuce growing in a nutrient film technique setup

Advantages

Constant Flow and Circulation

The constant circulation of water prevents stagnation and inhibits the growth of fungi and/or algae. Plus, nutrient-rich water is constantly supplied to your plants.

High Oxygen Availability

 Your plant roots are highly oxygenated due to the positioning of the plants in an NFT system. This is because parts of the roots are suspended in the water while other parts are exposed, allowing oxygen absorption and gaseous releases.

No Grow Media

Due to the constant exposure to the nutrient-rich water and the structure provided by the PVC piping in an NFT system, there is no need to use grow media.

Easy setup & Usage

This system is favoured by many farmers who are looking to optimize space or start out with an easy aquaponics system. We highly recommend an NFT set up for the beginner aquaponic hobbyist.

Mauritius (8)

Disadvantages

Limited Choice

Due to the setup of this system, there is a limited list of plants that grow well in an NFT setup. Smaller vegetables and leafy greens work best in this setup as their root system is small. However, larger vegetables or fruiting plants would struggle due to the limited space for plant roots.

Root Blockage

As your plants get bigger their roots can start clogging up the piping. This can restrict the flow of water to the other plants in the system and can lead to nutrient deficiencies.

Temperature Fluctuations

Due to the small amount of water running through the PVC pipes, the water is more susceptible to temperature changes. Your water can quickly cool down or heat up while running through the NFT. So, ensure to take regular temperature readings to try to gain some control over the fluctuations.

Your yield relies on your pump

If you lose power for whatever reason (Loadshedding or other inconveniences) your plants will not have any water pumping through the NFT system. Therefore, you could have some dehydration and nutrient deficiency issues on your hands. Make sure you have a backup generator or maybe give solar a try to prevent any loss in yield or degradation of plant health during a blackout.

 To conclude, whether you are just starting out or you are an experienced aquaponic farmer. We highly recommend giving the Nutrient Film Technique a try. If you are keen to get started with some NFT systems, why not book a consultation with us or check out our shop for some home systems to get you started.

Happy growing!