What is NFT?

N.F.T., or Nutrient Film Technique, is an efficient method of growing plants by providing a slowly moving film (stream) of fertilizer solution (nutrient) to roots in a flat-bottomed, gently sloped channel (the gully). The plant is started in a small root cube in which it remains for life, and is placed in pre-drilled holes in the gully. With the help of a small submersible pump and gravity, the nutrient solution is constantly recirculated through the gullies and back to the reservoir. This provides a constant balance and optimum conditions for thriving plant growth.

Our NFT Gully Kits use two distinct shapes of gullies, made for different plants. The 2"x4" gully is best used for lighter weight and "head-type" plants such as fancy lettuce, herbs and other short crops.

The 3"x6" gullies, which we call Rockwool gullies, are best used for heavier and longer term plants such as tomatoes, peppers, strawberries & cucumbers. These gullies have specially routed square holes that accomodate 3 1/2" Rockwool cubes, which provide plant support and help keep the roots moist.

Points to remember when installing an NFT hydroponic system

A. Your nutrient tank must have a fresh-water valve, fitted to makeup and keep up the initial volume of liquid in the tank.

B. A venturi oxygenation system should be installed.

C. The nutrient transport pump must be free from any corrosive or contaminating materials. Make sure you get one which is adequate in size for your operation. Also control taps should be installed in the feeding system to get adequate flow to each gully or feeding trough.
D. NFT gullies should be flat-bottomed. Lettuce should have 4+ inches on the bottom; tomatoes, pepppers and cucumbers need 6+ inches. The gullies must be constructed so the gullies remain flat.

E. The gully must not sag along its length and should be no more than 50 feet long with a slope of 1:40. Others claim twice that but they may be stretching the limits of NFT.

F. A maximumm of 34 fluid ounces per minute should be the nutrient flow rate down an NFT gully. This will provide the necessary liquid film to provide maximum growth and air to the root systems of the plants.

G. NFT gullies must be covered to prevent algae from growing on the root systems of the plants. But you still must provide some small openings around the stem entry to allow fresh air into the gullies.

H. Make sure the plastic you use for the gullies is not toxic to the plants. To test any plastic (film or pipe) place a piece of it into a cup of boiling water and sniff the air above the mixture. You may have a problem if you can smell plastic or when after cooling you take a small sip and taste plastic.

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