&NFT stands for nutrient film technique. It involves a thin, steady stream of nutrient enriched water to flow across the bottom portion of a plants roots. This allows a constant supply of water and nutrients for the plant, and a rich supply of oxygen in the moist air above. These conditions are perfect for growing hydroponically.
NFT usually involves a trough or tube with holes drilled in the top to place the plants. Inside the tube, water is allowed to flow through and over the roots.
This design helps to conserve water, as the water is never directly exposed to the outside light, and keeps the plants happy with a steady supply of nutrients and water without drowning them.
Most NFT systems do not use a growing medium at all. The roots are left bare and grow wildly throughout the tube or trough where the water is flowing.
Why use NFT?
NFT is a great option for growers looking to grow a medium to large number of plants. This is because, with the use of only a single pump to feed water into the system, this water naturally drains down the tube feeding a huge number of plants. This water is then collected at the end to go back into the reservoir where it is then pumped through once again on an endless cycle.
What Are the Benefits of NFT?
1. Conserves water
Because the water in an NFT system is completely contained within the troughs and reservoir, and not exposed to the hot sun or grow lights above, the only water loss that happens is through the perspiration from the leaves itself. This helps to conserve water levels.
2. Conserves energy
NFT does not need high-powered pumps to run smoothly, and because the water is blocked off from the direct heat of the sun or the grow lighting, it does not take much to keep the water from getting hot, which means there is no need for water chillers. This is more of a benefit for much larger grows as it is relatively easy to keep small scale grows cooler anyway.
3. Produces great results and high yields for most plant species
NFT has been tried and tested, and it is well known to deliver powerful results. A large portion of large scale greenhouse operations uses NFT for this very reason.
4. Requires no medium
Because in NFT the roots are directly trickled with water, there is little need for a medium. In fact. This saves money and keeps harvesting your plants simple.
5. Many plants can be connected and fed using only one small water pump.
Water is pumped up to the beginning of the NFT trough at a trickle rate (very weak), it then follows the pull of gravity down the trough which can be extremely long as is the case with large greenhouses. Because these systems use gravity to trickle the water across the roots, it does not matter how long the water travels before re-entering the reservoir below. This means a very large number of plants can be fed off the same pump size.
What are the challenges of NFT?
NFT offers many benefits but does bring with it some challenges. The main one is that since there is no medium for the roots to grow in, there is almost no water buffer for the roots. If the pump burns out or stops working and water is not fed to the roots. The plants will dry out and die very quickly, especially under a hot HID grow light or the sun. This can be alleviated by ensuring proper maintenance is done to your system, and have the pumps filter checked every few days to ensure it is not accumulating too much debris or becomes clogged. Water sensors can also be found, which will trigger a sound when they remain dry for too long.
The Challenges of NFT:
1. Unprotected roots are vulnerable to pump failures
Because so many plants can be fed off of a single pump, a failure to this pump can be catastrophic. The other major influence in this is the lack of a medium for the plant's roots. This means their is a lower degree of resistance to the lack of water. Pump failures with these systems need to be addressed immediately, and many professional growers keep spare parts, and even spare pumps around just in case a pump fails and a new pump can not be purchased right away.
2. Not all species are suitable for this system such as most root crops like carrot or potato
Root crops are not suitable for NFT systems, as their tuberous, thick roots will clog the pipes and can result in the death of all of your plants or damage to your NFT system.
What to Keep in Mind When Building Your NFT System:
NFT systems can be built at home using simple materials from your local hardware shop or purchased pre-built from hydroponic suppliers. Our NFT systems are perfect for beginners or those looking to get started quickly.
When designing your NFT system there are a few things to consider:
1.What crop are you planning on growing?
Some plants such as tomatoes and other herbs can have extensive root systems which may grow to clog your pipes. For these, it is beneficial to use larger troughs or tubes. Even better are the use wider, flat trays for plants like this to allow the roots to spread out and avoid clogging.
2. How many plants are you planning on growing?
NFT can accommodate many plants in the same system. A common method of fitting many plants into the same system with a single pump is to incorporate a tiered system. Each section of pipe or tray will drain off into another one going the opposite direction in a zigzag pattern. This has the added benefit of improving the efficiency of the lights used to reach the plants below it.
3. What is your budget?
NFT can be made using cheap materials such as PVC pipes or gutters. These cheap materials work great, and are highly cost effective, but for best results we recommend using a system specifically designed for hydroponic growing. These more expensive systems pay themselves off by reducing the energy requirements for your grow by maximizing surface area and allowing the use of smaller more energy efficient pumps. They decrease water loss through evaporation and reduce the chances of disease or pest infestation with clever designs that keep the system as sealed as possible to minimize the point of entry for pests and disease.
