Nutrient film technique (NFT) is an hydroponic technique that recirculates water in a thin stream called a “film” over the growing medium and plants.
What is nutrient film technique?
Nutrient film technique is a hydroponic method of growing plants that involves periodically passing a shallow stream of water and nutrients over the plant roots. Unlike other forms of hydroponic gardening, nutrient film technique does not use a medium such as rice husks, expanded clay pellets, or other inert materials to support the plant roots. The lack of a medium is said to give plants in nutrient film technique systems greater growth potential.
The nutrient solution flows down a channel that is lined with a material such as polyethyline plastic sheeting. The channels are inclined at an angle to the horizontal, so that the solution always flows down-hill. The plants are held in place with expanded clay pebbles, or another substrate.
A small amount of oxygen is added to the water at regular intervals to prevent the roots from rotting. A pump circulates the nutrient solution and is turned on and off at regular intervals.
The roots hang downwards with only a thin film of water flowing over them. They remain moist, but do not stand in water. The plants get all their water and nutrients from this thin film of flowing liquid.
Because only a film of liquid passes over the roots, this system requires less water than other hydroponic methods and is thus more efficient at producing crops than other techniques.
Things you need to have a successful NFT system.
1. A pump to circulate the nutrient solution
2. The nutrient solution itself (mix of fertilizer and water)
3. A reservoir to hold the nutrient solution
4. A drain plug, to let water out when you need it to
5. A return pipe, so that the pump can bring the nutrient solution back into the grow tray when it’s done moving through the system.
6. A grow tray, with holes in the bottom and a lip around the edges to keep your plants in place
7. Netting pots, which allow roots to grow down through them while keeping soil from entering your system
8. An overflow pipe, which allows excess nutrient solution to escape when there’s too much water flowing through your system
The nutient solution
Nutrients are a very important part of growing healthy, productive plants. The nutrient solution for NFT is made up of two components: water and nutrients.
The quality of water used for making the nutrient solution is of the utmost importance. Water should be oxygenated by running it through an aerator (similar to an aquarium pump) for 24 hours before using it. Additionally, water should be used at room temperature (approximately 70°F). This will help prevent plant shock when you change out your nutrient solution. Tap water can be used if the pH is between 6.0 and 7.0; otherwise, use distilled or reverse osmosis water.
There are many different types of hydroponic nutrients available today, so choosing the right one can seem difficult but it doesn’t have to be. It is best to choose a hydroponic nutrient that has been formulated specifically for hydroponics. However, if you want to use a conventional fertilizer in your hydroponic system, keep in mind that not all fertilizers are created equal and some may have too much nitrogen or salt which can damage plants and block root growth. It’s best to avoid using fertilizers formulated with quick-release nitrogen sources like ammonium nitrate
The water return pipe and fittings
NFT is a hydroponic method of plant production by means of a “nutrient film” of water containing all the dissolved nutrients required for plant growth. In an NFT system, the nutrient solution constantly runs past the bare roots of plants in a watertight gully, also known as channels. The rate at which the nutrient solution flows is adjusted to approximately the same rate as that at which the roots can absorb water.
NFT is one of three main types of hydroponics; it is different from media-filled systems and drip systems. NFT consists of a very shallow stream of water with nutrients, which are constantly cycled through a closed system of PVC pipes (channels). The water flows past the bare roots, providing oxygen to the roots while simultaneously allowing uptake of water and nutrients. A pump provides flow within the channel and returns excess solution to a reservoir for reuse.
The optimal depth for an NFT system is around 5 mm. This is deep enough to prevent exposure to air (and thus evaporation) but shallow enough that adequate oxygen can be absorbed by the roots. A typical flow rate for an NFT system is 2–5 times per hour.
Hydroponic balls are perfect for nutrient film technique.
The benefits of hydroponic balls are many. They are very easy to use. They are small and light, so they can be used in a wide range of hydroponic systems. They are reusable, so you don’t have to throw them away after one use.
This is a good example of a short description for the blog section above. Hydroponic balls can be used for nutrient film technique, which is a popular way to grow plants with hydroponics. This is an example of the text that would appear under the blog post title and before the more link.
I think the key takeaway should be that you will have to experiment a lot in order to get the right parts and put them together. I really do hope this list helps you get started with NFT, it certainly gave me a sense of direction when I first started researching it.