Nutrient Film Technique Hydroponics

Nutrient film technique (or nutrient flow technique) provides a continuous flow of nutrient solution over the plants roots. It is the 'stereotype' of hydroponics systems. When most people hear the word, 'hydroponics' they envision a nutrient film technique system.

For a homemade system this can be a mite complex. For materials you would definitely need a water pump, a container holding nutrient solution, a long trough of some sort to run the solution through (and back into the container) and some means to anchor the plants sitting in the trough.

I have not personally experimented with a nutrient film technique system but it is do-able.

Disadvantages:

• Such a system would not be as compact as other systems mainly due to the long trough to grow plants in.
• Plants roots hang down into the trough (there is no growing medium) so without constant running solution to wash and feed the roots, they will dry out and the plant will die. In other words, a power-outage can be disastrous.
• Plant roots can easily clog the trough and impede the flow of nutrient so would need to be periodically trimmed.
• Various sources cite plant yield of a homemade nutrient film technique system as only moderately successful.

Get 2 two inch PVC pipes each 6 feet long. These become the troughs. Glue PVC end-caps on each end of both tubes and into each end-cap drill a hole into which a tube will be inserted. Place these holes near the bottom of the end-caps. Get a 10 - 15 foot length of plastic or rubber tubing of the right size to fit into the holes drilled into the end caps.

Now drill holes into the top of the PVC troughs (top meaning that the end-cap holes are aligned on the bottom). Drill as many holes as needed along the length of the pipe spaced the proper distance apart that you want your plants to be. A good 'rule of thumb' is to take the distance between plants as specified for a dirt garden and half it. Your plants will be placed into these holes. You may find you will need some kind of support placed into these holes such as plastic screening to support your plants. You'll have to get creative concerning this.

Next, use a 5 foot piece of tubing and silicone one end into the end of 1 pipe and the other end into the second pipe. Now lay the pipes side-by-side in your growing area about 3 feet apart (the pipes are now connected on one end) on a support at least 3 feet off the ground. Incline the connected end a couple inches.

On the unconnected end silicone in a 5 foot length of tubing and connect the other end to a water pump we will refer to as the 'intake tube'. On the last unconnected end silicone in the end of another 5 or so feet of tubing we will refer to as the 'drainage tube'.

Purchase a large plastic clothes storage container of somewhere around 12 - 15 gallon capacity (Walmart has them). Fill this container with water, mix in the proper amount of hydroponic fertilizer, submerge your pump, connect the intake tube to it and dangle the drainage tube into the storage container.

Just plug in the pump, put in your plants and you should be in business. Pumped in water will flow up tube #1 washing the roots of each plant with nutrient, cross over through the end connecting tube and flow down tube #2 back into the nutrient solution.

As a suggestion, allow the drainage tube to hang above and not in the nutrient solution so it will splash back and become aerated.

Also figure out how to support your growing plants because they will grow fast and big quickly. You will need something or they will just fall over.

A word of warning: do not underestimate the weight of your supported plants - 20 or more very large tomato plants will actually exert a few hundred pounds of pull so plan accordingly...

I have to add a disclaimer here....I have never built a system of this type, but if I were to build one I would follow the directions I just provided. This means that I can make no guarantees as to whether the system design will work.

But, if you have made it this far you are probably ready for a little experimentation so .... go for it!


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