NFT Hydroponics System Building; Requirements
Today, we learn to build an NFT Hydroponics (nutrient film technique) basics, pros, and cons. N.F.T (nutrient film technique): A successful hydroponic system: Your dream of having a beautiful green space in your home can be turned true by means of the science of hydroponics that too when you can own a garden that you can both enjoy and use. So, today we are back with a complete guide about N.F.T another yet important hydroponic system among the six.
N.F.T stands for nutrient film technique is a hydroponic growing method in which a small, shallow stream of nutrient-rich water is re-circulated over plant roots through a channel, drain, or tube. This method of hydroponic farming was evolved in the 1960s by Dr.Allen Cooper, since then NFT has become a standard practice and one of the preferred methods of hydroponic gardening. The nutrient film technique (NFT) is quite similar to the ebb and flow hydroponic system as their principle utilizes a pump to move nutrients in a continuous, constant flow. Among these hydroponic systems, N.F.T differs with respect to its configuration the only difference is in case of N.F.T nutrient solution directly flows over the plant’s roots unlike the flood and drain mechanics of Ebb and Flow system.
In the realm of soil-less gardening, the nutrient film technique system (or NFT system) is also quite admired by hydroponic growers due to its effortless yet effective design. The nutrient film technique is commonly used for smaller and quick growing plants like diverse varieties of lettuces. Apart from lettuces, commercial growers are also opting this system to grow various herbs and strawberries.
The principle behind working of N.F.T
The nutrient film technique makes use of shallow tubes that are a little angled so that the pump moves the nutrient solution to the higher segment of the system. The nutrient solution steadily moves by the action of gravity to the lower segment. A tube system with holes made for the plants is used as an alternative of trays, primarily because this arrangement is easier to angle for appropriate flow over the plant roots.
Although there are a variety of ways to devise a nutrient film technique system; however, all of them follows the idea of a very shallow nutrient solution driving down through the tubing directly to the plant roots. The bare roots of the plants will effectively take up the nutrients in the solutions when they come into contact with the water.
Read: Ideas for Modern Gardening.
Most of the growers grow plant directly through the holes, but net pots or plant baskets can also be installed in the setup, however many horticulturalists do not prefer using planting medium (e.g., vermiculite) with the nutrient film system. The roots descend through the net directly into the nutrient solution. The point to be noted is nutrient solution does not completely soak the plant roots. The film makes sure that the whole root is not submerged so the upper part of the roots remains dry hence less fear of waterlogging and anaerobic situations.
When you are using the nutrient film technique it is imperative to not try to cultivate heavy or large plants that need a lot of support this is because the plant’s roots are not in a medium that can uphold the weight of a heavy plant. In such cases, it is essential to use a self-standing trellis or any framework to support plants with heavy fruits such as tomatoes or melons.
NFT is considered an active system because it consists of moving parts. A hydroponic system such as wick system, which is tagged as the simplest hydroponic system is a Passive system because it contains immobile parts it just uses a cotton wick to transport the nutrient solution to the plant root. That’s why it is preferred and often used for demonstration purposes for students or as a simple do-it-yourself method for beginner home gardeners.
What you need to build a nutrient film technique system (NFT)
- Container to hold the nutrient solution (a reservoir)
- Submersible fountain/pond pump
- Tubes to dispense water from the nutrient pump to the NFT growing tubes
- Growing tubes for plants to grow in (also known as Channel or gully)
- Net pots to contain plants and growing media to start seedlings in
- Return system (tubing, channel) to direct the used nutrient solution back to the reservoir
In the NFT system, there are two main components: the grow tray (or channel) and the reservoir that contains nutrients dissolved in water.
- In the grow tray, there are net pots or plant baskets that contain the growing media (perlite or Rockwool) for providing support to growing plants and absorb nutrients from the nutrient solution. But in some cases, most growers don’t use growing media in the NFT system as the plant roots have had an adequate amount of moisture, nutrients, and oxygen from the system.
- The plant roots develop into a dense mat in the channel and the foliage sits on top, occasionally provided with support by a trellis arrangement.
- The NFT system uses a water pump to transport nutrient-rich water to the grow tray and a draining pipe to descend and recycle the unused water nutrient solution back in the reservoir.
And how does all this functions?
How a hydroponic N.F.T. system operates is quite simple. The Nutrient solution is pumped up from the reservoir. Each one of the smaller tubes runs nutrient solution to one side of each one of the growing channels/gully with the plants placed in it. The nutrient solution flows starting from one side to another because the channel is sloped slightly so the water streams downhill.
The plants in the growing tubes (channel/gully) are characteristically suspended above the water by placing seedlings started in starter cubes or small one inch baskets with growing media into small holes in the top of the tube. The grow tray is placed at an angle to let the water pour down towards the nutrient return pipe. The surplus nutrient solution will stream out of this pipe and move into another channel or tube, where it is re-circulated through the system again. The roots of the plants are suspended down to the channel where they make contact with the shallow film of the nutrient solution and absorb the nutrients from them. The thin film of the nutrient solution allows the plants to be watered but not entirely soaked. The thin layer (film) of the nutrient solution flows all the way through each of the channel having plants in it to the other side, passing by each plant and wetting the roots on the bottom of the channel. This thinness also permits the upper fraction of the roots to remain dry and have access to oxygen in the air without being water-logged. While the nutrient solution streaming through the channels is very shallow, the complete plants root mass remains moist from the roots being able to pick up moisture on the outside of the roots, as well as through humidity that’s reserved within the tube/channel. The roots that are suspended amid the base of the plant and the water level in the channel not just have moisture to access, but are also able to acquire plenty oxygen from the air surrounding them within the tube/channel as well.
Tools required to build an NFT Hydroponics system
As mentioned any N.F.T system consists of two main components:
The grow tray or channel and Reservoir
The grow tray or channel
It is required to facilitate all of the nutrient solutions to be passed to the developing plant roots; growers make use of slightly downwardly angled tubes or channels instead of the usual flat trays. Using tubes or channels also make it easy to set the grow tray at an angle which eases gardening and also imparts a different look to it. Mostly, the channels are made of impermeable materials such as a PVC pipe, plastic film or a round tube. PVC remains the first preference because of easy availability and it offers more space for growing plants. On the surface of PVC pipe, holes are made to fit the net pots or plant baskets and seedlings or plants are planted. You can place plants or seedlings in two ways. The first option is to place seedlings directly into the holes of your PVC pipe or channel. Another alternative is to put seedlings into net pots or plant baskets for better stability and then place them into the holes you can also growth medium in pots. Like I have mentioned previously, most of the growers don’t use growing media in the NFT system. If you settle on using it, make sure you don’t put them in excess into the net pots for the roots still deep enough to fall through the bottom. Apart from the seedlings method, you must check and trim the plant roots often to prevent extended long roots that may clog the system.
The reservoir of NFT Hydroponics
The reservoir is joined with the grow tray by means of a nutrient pump on the high end and a nutrient return pipe on the low end. Inside the reservoir, there is an air stone connected to an air pump outside to oxygenate the water by forming small air bubbles. The reservoir is used to hold the nutrient solution since the NFT system is a recirculating one. The reservoir size depends on the number of plants that you want to raise. Suppose if you wish for building a system of 40-50 plants, you will need a reservoir with a minimum 5-gallon capacity. It’s always recommended to have a little more volume capacity than it is needed rather than to be short.
Now coming to the most frequently asked question what plants to grow in an NFT system?
The NFT hydroponic system is most suitable to produce lightweight, fast-growing plants that can be harvested rapidly like different types of lettuces, kales, many oriental vegetables, and herbs as well. People have also successfully cultivated perennial plants like strawberries for commercial production. If you wish for producing heavy fruits like tomatoes or squash, you need a proper independent trellis system to hold up the plants. The NFT is not appropriate to plant heavy crops that require much support because the roots are not in a medium to hold a lot of weight.
Now let’s chatter about different strengths and weaknesses of the NFT
Strength of NFT Hydroponics (Pros)
- It makes the inspection of growing roots easy for observing any symptom of disease, feed adequacy, etc. due to the nonexistence of medium.
- Low water and nutrient consumption has been reported because of the availability of proper humidity and moisture
- Without doubts, the system is environmentally friendly first of it diminishes the risk of contaminating localized groundwater and second the water which is unused is recirculated back to the reservoir.
- Unlike other media based systems of gardening, you can stay away from problems related to matters such as supply and disposal.
- Relatively easy to disinfect and clean roots and components in comparison with other hydroponic systems.
- Plant roots can keep up a consistent pH and conductivity thanks to regular feeding (and associated flushing) that prevents restricted salt build-up as there is no stagnation.
- You can also build your system in different shapes and colors as a decorative piece in your living room.
- This system enables cultivation of a large number of plants at a time in the same system.
Weaknesses of NFT Hydroponics (Cons)
- The major limitation of this system is, the plants are very susceptible to interruptions in the flow of water from power outages or any other reason. The plants will begin to wilt and stressed very quickly any time the water stops flowing through the system.
- In a newly planted arrangement, when exposed to intense sunlight, the channels can heat up faster than the root zone would heat in the usual growth medium. However, the constant flow of nutrient solution does have a cooling effect.
- The channels can become choked-up by roots of vigorous-growing plants hence root growth has to be checked and trimmed at certain interval of time.
- Pump failure can cause the death of plants.
- Not suitable for growing plants with large tap-root systems such as carrots.
That’s all folks about NFT hydroponics system.