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Grow Room Humidity Problem

Discussion in 'Grow Room Design/Setup' started by Nor-Cal-Bud, Mar 1, 2008.

  1. Hello Fellow Stoners,
    I'm in my 7th day of flowering and have a small issue with humidity in my grow room. The room is built in my garage and temp variations are present from night to day. I flower at night in an attempt to minimize the heat that is coming on with spring.

    Here' my issue, I never had a humidity problem while vegging, but now that I have introduced Co2 and sealed the room, I average about 80-90% humidity. From what I have read, you need to seal the room, introduce Co2, have plenty of air circulating. I am using the Air-3 Environmental Controller.

    I've attached a drawing of the growroom, then also added a few pics, as the drawing is a little manipulated.

    So I guess MY QUESTION is, how do I attain and keep constant a lower humidity level?

    ABOUT THE IMAGE -- The BROWN BOX is the grow bed (4' X 14') filled with Coco

    Attached Files:

  2. Here's an older pic of the room at about day 25. I went in to take more pics, but missed the opp, the lights were off.:eek:

    ONE THING TO NOTE>> my Fresh Air Intake is only 6" and the fan the sucks out the old air is 6". I'm thinking I may need about 4 Fresh Air Intakes.

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  3. Where does your intake come from if i may ask ?

    if its from inside the house, where are you pulling from ? and you just go ahead and drill 4" Holes in your wall? no problem ? or do you hide it?

    im just curious if you have intake from another room, is it possible for that room to smell alot like MJ?
  4. The fresh air comes from the garage. What I have done is built the box inside my garage. All "used / outgoing" air is vented up into the attic.

    The air going into the growroom is ambient air from the garage (both light cooling air and growroom air)

    I have revised the drawing and added a few notes about the environment.

    My best guess is that I need more "fresh air intakes"(red) for more efficient / faster removal of high humid air.

    Attached Files:

  5. Increase the air intake and outtake, or just buy a dehumidifier from wally-mart for like 20-30$, and set it on high for such a big grow space.
  6. By increasing the intake / out put, wouldn't that defeat the purpose of the Co2? or do you really exchange the air about every hour while using Co2?

    Thanks for the replies
  7. if the room is sealed and the only exhaust/intake is used for cooling the lights then it shouldn't suck out all the c02.
    Be careful with dehumidifiers they put off a ton of heat.
    what kind of fan are you using for exhaust atm and how much ducting is it pulling through?
  8. I'd say pretty much sealed, there are a few small leaks.

    As for the fan, I am using 1 ea. 6" Ecoplus for the lights and 1 ea. 6" Ecoplus for the Carbon Filter that exhausts the room.

  9. I introduced a small heater into the room and am tracking my temps and humidity levels about every 3 hours. Looks like the heater is helping out some. Once the lights come on I'll get a pic
  10. ok, I'm at day 10th of flowering and took readings on the humidity / temp. all day. Seems like I needed to tweak the Air-3 a little. I took the humidity down and just having to evacuate the air in the room a little more than I would like, but hey, it's working.

    My temps / humidity levels are:

    60 deg (low) - 73 deg (high)
    50% humidity (low) - 84% humidity (high)
    The average humidity is now about 60%. The 84% high I got was what prompted me to tweak the controls on the Air -3

    Here's a few pics I got this morning


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  11. Dude this seems like right up Rumpleforeskins alley, you need to ask him! Hes the man on garage room and co2 grows.
  12. love you idea but the meaning of a seal grow room is there is no in or out vents you control everthing from inside the room. meaning add a co2 controler, dehumidifier and a/c unit. if you do it without all the right equ. you will not be getting the best out of your equ. to keep your humidty down you will have to vent more that means you have to use more co2 and you waste alot of it. so vent more or get the right equ.
    good luck
  13. So I worked thru the humidity with a de-humidifier. All went pretty good, but now that I have removed the co2 and de-humidifier, I have a small case of Powdery Mildew creeping in. Nothing that can't be managed with a fogger /atomizer and a little greencure.

    Here's a pic of where I'm at with it

    Attached Files:

  14. Just wondering, Did you clean that re-bar before bringing it into the room?
  15. It would seem to me that you would want a CO2/humidity/temp controller. When I ran CO2, it was close to the same set-up, but we had an exhaust plugged into the controller. When the humidity went high, it would shut off the CO2 and exhaust till humidity went down. It's been a while since running CO2, but if I remember correctly, that is what we did.
  16. Nope, left the ree-bar dirty from last years outdoor grow. Never had a pest problem, just a little powdery mildew.

    I was using an Air-3 Atmospheric Controller, but about 30 days into flowering I noticed it had an AMBER LIGHT on the face of the unit that never turned off, even in the dark it was on. I was a bit frustrated so I took all the Co2 equipment out. I ran the existing bottle dry manually and everything bounced back. I a little strecth on a few of the large tops, but it really popped back.

    I have em drying right now and think I should see about 3.0 lbs on this one. with a 33 day veg.
  17. Your set up looks GREAT!! VERY similar to my planned set up with a Cap PPM-3 and burner.

    I hope your lights were raised just for the pic(12-18" works best for me).

    If you cannot control the RH W/O exhausting the moist air and wasting your precious tank co2,you should invest in that multi controller to shut down any exhausting during the gassing phase and cycle the two as to save the gas,the temps will rise at that time and the plants will love it at 1500PPM of co2.

    Another method of absorbing excess RH is a silica product in a mesh bag (like in med bottles) which can be reactivated in a microwave to dry and reuse,never used it but read about its use.

    Love seeing grows so similar to my own.:D

  18. hey man, did you have any problems with your carbon filter? Ya know with your high humidity levels and all :smoke:
  19. #19 blindbudsmoker, Oct 27, 2010
    Last edited by a moderator: Oct 27, 2010

    20-30 doller dehu wont do shit once they get moving

    also not sure where in nor cal u are but if u are inland the heat will kill you this summer and u will need to get a ac in thier, once thats done u can close off that intake and run co2 full time. surprised u made it as long as u did with no dehu. in a 4 light room our humidity hits 100% in 30 minutes of the lights going off without the dehu on.

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