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Optimal lighting for seedling?

Discussion in 'First Time Marijuana Growers' started by JHOS, Sep 21, 2020.

  1. Is this 40w LED grow light good enough for seedlings? Or should I use my 250w MH light?


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  2. 250w MH
     
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  3. Ok might as well return that LED thing then. Do you have any tips on how far the light should be from seedlings?


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  4. 40 inches should suffice. I would lower it once a day and find the sweet spot.

    I had a 6ft high tent and used a 600w MH from sprout. Very night tight nodes throughout veg
    Had it high as it went and day by day lowered it
     
  5. Thanks! How do I know when I’m too low?

    I have another set up with 630w Ceramic MH light (two 315w lamps). Make most sense to use that instead one they sprout?


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  6. I give them the most I can early as I can. Seedlings it's a little harder to tell, they will stretch if they need more.

    Look at them now, the leaf shape, healthy, as you lower if they start to fold like a taco or bleach, raise up more.

    My plants never stretched with the 600w at 40inches, but I was able to get the light to around 23 inches before they stressed. So I kept it around 2ft.

    Seedlings I think around 30 inches, once they reached veg they could take a little more if I remember correctly
     
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