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How many watts for 4 plants?

Discussion in 'Indoor Marijuana Growing' started by Mashiro, Apr 11, 2012.

  1. As the title states... how many watts of light would you need for 4 plants in a tent similar to mine?

    Tent in siggy.
  2. #2 will3117, Apr 11, 2012
    Last edited by a moderator: Apr 11, 2012
    600 hps its what i use for 4 plants, scratch that I use a 2x4x5 tent and scrog 4 plants, 2x2 im thinking 400 would work, also check amazon they have a sweet 600 dual hps and mh with a dimmible ballast so you can adjust to your best light range..
  3. Can't see the sig on the phone
  4. It's a 2' x 2' x 4' tent. For ventilation right now I only have a 6" duct fan. I'm saving to upgrade that right away.

  5. why would you need to upgrade? im running a 6" duct fan too, its 500 cfm does good on the temp control venting for a 600 hps, with passive intakes and 3 9" fans for air flow...I was thinking two 6" duct fans and filters, but seems like overkill, so i stored the extra set for back ups.
  6. What size is your grow area?
  7. it is 2x4x5 tall
  8. I dunno, I've just always had the impression that duct fans won't do the job. Also, can you attach a carbon filter to a duct fan?
  9. im just going to post this just so i make sure we have it right

    Length x Width x height = 2 x 2 x 4, right?

    with a tent that small all you need is 400 watts... that's 100 watts a square foot(think more of footprint rather than cubic feet) that being said you can never have too much light(unless its too close) but you can have too much heat....

    maybe consider getting a 600 digital ballast that you can turn down to 400, this way if you can handle the heat in the tent you can leave it on 600, and if not dial it down to 400

    problem solved?

  10. duct fans really should only be used in bathrooms, that's why their nick name is a fart fan... and thats all they pretty much move...

    use inline fans...

    that being said i've seen some pre-made box's that use ducting fans and they say the temps are stable... never seen them first hand though... and i'd imagine that they would fail more so than inline fans....
  11. Thanks, man! I did not know you needed 100 watts a square foot. Also, if I did upgrade to a better exhaust fan to control temps, what sort of CFM range am I aiming for in a new fan?

  12. im running one 6 inch duct fan with carbon filter its rated at 500cfm, it sucks air across the 600 watt hps, the 3 9 inch fans are purely for air circulation ive found the more air you move the cooler it stays and the happier your plants are, im growing indicas (Crimea Blue) using scrog to keep the height down.
  13. 600 would be perfect for some nice large, high-yielding ones. A 400 would suffice though if u dont need like an lb in one run.
  14. Mine is rated at 250 CFM.
  15. I should have posted that 50 watts a foot by some is considered the minimum... and a six inch inline fan should be strong enough to cool the light and exhaust the space
  16. carbon filter (if inside the tent) > ducting > duct fan...duct fan > ducting > carbon filter (if outside the tent)...but I don't know if there would be enough pull/push, never tried it personally.
  17. My tent is just a little bigger than yours (2x3) and I'm using a 400w to veg, 600w to flower. I've got 4 plants in there right now, and it seems like it'll be pretty crammed when they're bigger (might have to move one or two to my big tent). I think my fan is 170cfm, and it cools my lights and ventilates just fine. Not sure how the 600w is gonna do in there...guess we'll see.

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