400w MH veg distance? HPS vs MH?

Discussion in 'First Time Marijuana Growers' started by Ganja42449, Apr 1, 2020.

  1. How far should I have my 400w MH wing reflector light set up from my plants. And wondering personal preference for how vs MH for vegetation. I've only grown with CFLs and LEDs in that past. The light is currently hung 2 1/2 feet from the tops. Thanks for any replys

    Sent from my BLU R1 HD using Grasscity Forum mobile app
     
    • Like Like x 1
  2. Autos or photos?
     
  3. That's probably about right at 2.5 feet. Great veg bulb especially a hortilux blue. Not so good for flowering.
     
    • Funny Funny x 1
  4. [​IMG]
    old school and just as good today

    400w I use 5 inches to get 66k Lu keep a fan close by and check temps after 30mins imo

    do note 2.5ft /29inches is not worth bothering with ,...lol

    yes its the first timers fourm ...lol
     
    • Like Like x 1
  5. 5 inches from the tops? Lol def not gonna be able to do that

    Sent from my BLU R1 HD using Grasscity Forum mobile app
     
    • Like Like x 2
  6. So should.i just leave the light where it's at lol

    Sent from my BLU R1 HD using Grasscity Forum mobile app
     
    • Like Like x 1
  7. #8 old shol4evr, Apr 1, 2020
    Last edited: Jun 16, 2021
    delete
     
    • Like Like x 1
  8. Get it as close as you can without em getting hot. They will stretch with the light up 2.5 feet, but definitely "worth bothering with" since i can veg 48 plants under a single mh bulb and get them 5 feet tall before they go outside. To each their own. If you are doing the flowering inside, yeah, get it as close as you can without getting too hot. 20200331_153159.jpg On a light mover.
     
    • Like Like x 1
  9. Yeah go ahead and use your MH. You'll be using it for a while depending on how long you plan on vegging them for. Idk how many plants you're doing. For my first grow, I started my photos with a t5 fluorescent. Veg'd them for 3 months so I had to switch to a stronger light when I transplanted to 3G pots. I'm doing autos right now for the first time for my second grow and there was some advice thrown out to me about starting with my HPS with them. I have a 1x1000w though and you have a 400w. 400w I'm pretty sure is weaker than my t5 at full. My 1000w light is also a reflector light.
     
  10. Lower it until you get a temperature of about 28 degrees right above the plants. Test around the top of the canopy to find the hottest area. It's not always directly under the bulb. Sometimes the reflector can cause a hot spot to the side. As long as no part of the plant gets hotter than 28 degrees, you want the light as close as possible
     

Share This Page