600 hps or 400 MH for 4x5 Grow Room

Discussion in 'Growing Marijuana Indoors' started by Fred K Lueless, Sep 3, 2008.

  1. I am currently running a 400 watt MH in my grow room. It is 4X5 and 5.5 feet high. I keep 12-15 plants in the Grow Room. Flower room has a 1000 Watt HPS and is 10X10.
    I am wondering if swapping out the 600 watt HPS for the 400 Watt MH will be productive, Will it be worth the added power cost. I use Fow Farms Happy Frog Soil in 5 gallon pails. They get fed every watering (according to package directions) with Fox Farms Gro-Big in the Veg. Stage and Fox Farms Tiger Bloom and Big Bloom in the Flower Stage. If that makes any difference.
  2. in my opinion, the 600 watter would be a good improvement

    i have one myself in a smaller grow room than yours and it works great, just as long as you have good ventilation

    the extra lumens would really make a difference in my opinion

    a 400 watt is, what, 55,000 lumens?

    600 watt is 95,000 lumens, almost as much as a 1000 watter

    i even use the 600 watt for seedlings, gives them a better start and makes for a stronger plant. They can even hack it when the light is about a foot away from the seedlings with good ventilation!

    the closer the light is to the plant the better. Lights loose a lot of lumen power the further away they are

    your choice, but 600 watt will definately give stronger, faster growing plants

    plus the cost is about the same

  3. Cool, I already have the 600 watt lamp and ballast. Just a matter of plugging it in in the 400's place. The Red end of the light spectrum will be OK for the Veg, stage? I don't thinkl it will make a whole lot of difference but I like to hear from folks that have more time and experience at this than I do.
  4. i agree, i think it is easily possible to get the same results with a 400 watt by putting it closer to plants, but obviously there is more potential with a 600

    wait for some different opinions

    for me though, its basically the same running costs for more lumens

  5. yea the 600 would be better for your babys in the long run
  6. #6 lucky27, Sep 3, 2008
    Last edited by a moderator: Sep 4, 2008
    hps mh........ contrary to what most people say... They both have their upsides and down however you can use either and still grow good plants. Yes to have both of them would be a huge benefit BUT it's not a requirement. It more personal preference
    The idea is to utilize as much of light as possible as waste as little as possible.
    The amount of light admitted from the bulb is measure in lumens. So are more effective that others. Divide a lamps lumens by the wattage to find its lumen per watt ration. this will allow to compare the efficacy of lights at different wattages. There's more to it than just how bright your light is.

    20-50watts per sq ft minimum

    HID bulbs will cover:

    5 - 12 sq ft

    8 - 20 sq ft

    12 - 30 sq ft

    20 - 50 sq ft

    Approximate lumen output for HID's

    watts....Metal Halide......High Pressure Sodium
  7. Have you made any decisions yet?
  8. I Think I will wire in the 600. It can only speed up the Veg process and perhaps tighten up the plants a bit.
  9. #9 brown2rl, Sep 6, 2008
    Last edited by a moderator: Sep 6, 2008
    i'm pretty sure you only need 3,000 lumens/ft^2 for optimal CO2 enrichment. so, that means you would need only 48,000 lumens for one 4x4 area. i would just go with two 250 watt hps lamps at roughly 25,000 lumen outputs a piece. that'd give ya just over what you need to make up for the extra square foot plus, more light disbursement with two lamps

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