Nutrient film technique: how NFT works
A thin stream of solution runs along a sloped channel past the roots.
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How it works
In nutrient film technique, or NFT, plants sit in holes along a slightly sloped channel. A pump lifts nutrient solution from a reservoir to the high end of the channel. A thin stream flows past the roots and drains back into the reservoir.
When the pump stops
In NFT the roots sit in the moving stream, so the flow stops when the pump or the power stops. Read the maker's instructions on pump stops and power cuts before you start.
Pump, power, and water
CPSC says a GFCI "is designed to protect people from severe or fatal electric shocks," and that ground fault protection is used "especially for circuit outlets in particularly vulnerable areas such as where electrical equipment is near water." Use a qualified electrician for any wiring. CPSC says to test every GFCI "After installation," "At least once a month," "After a power failure," and "According to the manufacturer's instructions." If a test fails, CPSC says to "Contact a qualified electrician."
What we do not say
We do not give channel slopes, flow rates, or nutrient strengths. Follow the maker's instructions and the nutrient label.
This is general information, not legal, electrical, or safety advice.
Sources: CPSC, GFCI Fact Sheet (Pub. 099).
FAQ
General information only. Water and electricity are a dangerous mix: keep plugs, cords, and connections away from water and follow every maker's instructions. CPSC says a GFCI "is designed to protect people from severe or fatal electric shocks" and to test every GFCI "At least once a month." Use a qualified electrician for any wiring. Keep nutrients and other chemicals away from children and pets. In an emergency, call 911.
Next: deep water culture
Roots hang in the solution.
