NFT, Timing, Oxygen, 12V and NFT problems

Author: Scott  


Hi, please advise me about your NFT channels . I want to grow larger plants so the widest channel would be my choice but I am not sure of the spacing. I would order an extra top to modify the spacing myself.

The watering times you give are odd as all I have read says to run continuously. Could you perhaps give me more information about this.

I am experienced with Run to waste and want to change my system and my grow room is 1.5 x2.5

I am not interested in sea of green or scrog but larger non bushy plants.

Please can you supply 12v water pumps for nft or do you have a fail safe system to cope with power failures.


  1. 150mm x70mm channel and lid is $27 per meter
    1. Lid only is $10 per meter
  2. 225mm x 70mm  channel and lid is $34 per meter
    1. Lid only is $12 per meter
  3. Most of the commercial growers in Queensland use timing to increase air around the roots, and complete drainage.
    1. 15 minute break is not enough time for roots to dry out but roots can drain and get more airation.
    2. Running continuously is fine if the water is below 25 degrees and can therefore hold water.
    3. Above 25 degrees the water won’t hold much oxygen and allowing temporary drainage for say 15minutes is the easiest way to get air into it.
    4. If there is a chance of root drying out, say because it is so hot, either drain for a shorter period or keep running through a hot period/ hot part of the day.
    5. NFT was designed for HEATING plants in England. It is a problem keeping the temperature down for Australia. Commercial growers often have 45+ degrees – and big root problems if they do.
  4. 12V is a good idea, but the lower wattage and DC design usually results in higher failures.
    1. The Aqua One is 240V and do not fail but are at the mercy of power supply.
    2. Perhaps get a UPS (Uninterrupable power supply ($90?)) designed for a computer. That could solve the issue if you are worried about power.
    3. Inside, if power cuts out so do lights, so plants don’t get too problematic if its 15mins to 45 mins. Several hours or Overnight could be an issue with plants taking a day to bounce back… Its never been a big enough issue for us in SE QLD to fix it.
  5. NFT is a very unpopular system here, with 99% of growers using media based system due to
    1. NFT being a lot more work and
    2. often more risky than other systems.
    3. My NFT here has been working fine for winter and spring. But from Last Thursday to Monday was all it took for rot to set in. Today I am putting in products to treat it, adjusting timing and I have even thrown about 20% of the plants out. It wasn’t anything I did differently, however, checking the roots and keeping them white is the key to NFT results. You can’t set and forget it.

I hope that helps.

Thanks Scott

Scott Andrew

Hydrocentre Pty Ltd Also Trading as Nerang Hydroponic Centre

4/50 Spencer Road Nerang QLD 4211

Phone 07 5527 4155

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