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Positronics Seeds - Purple Haze #1

Purple Haze #1

Constructed from Mexican, South Indian and Thai variety up until the '70, this plant posseses an incredible resin development. Deliver a clear and energetic high.

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Positronics Seeds - Blue Rhino

Blue Rhino Seeds

Blue Rhino is the outcome of careful selection among numerous plants from a classical breeding procedure that makes positive that simply one of the most powerful and exquisite hybrids more knowledgeable growers were demanding.

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Positronics Seeds


One of the first of the Holland seed breeders, Positronics has earned a solid and respected reputation. Positronics set out with the mission of ensuring that home growing supplies were available to everyone.

Controlling humidity, to high creating mold.

Discussion in 'Growth' started by retired?, Jun 16, 2012.

  1. Offline


    Inside Temp 70-80 deg, humidity 50%. outside Temp 40-75 deg, Humidity today 75%. Here in western WA. the rain has not stopped, it is still very wet here. I am starting to have problems with mold and I'm ready to flower. Soil grow. There is constant air flow through the room. I have a 16" osculating fan on 24-7. I removed all extra water from the room. I water about every 4 to 5 days.
    Today I plan to spend some time cleaning off leaves.

    Short of installing a De-humidifier is there a way to dry the intake air without adding a lot of heat to the room?

    Thanks for any help resolving this issue
    CamperDon likes this.
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    Hash O'Kief always Hashy

    it takes 7000 btu's of air remove 1 lb of water in an hour

    that's about 3 gallons a day

    get a small ac unit...
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    The AC unit is in the plan just not in the budget right now. I found a DIY over on grasscity using Calcium Chloride (salt). Interesting stuff. I use CC in my reclamation process at work. When I get it on the floor, the floor is always wet in that spot till I remove it all. I will give this a try until I get the AC unit.

    I did not know an AC unit would remove moisture from the air. Thanks for that info Hash. Would it be effective in the winter months?
  4. Offline

    CamperDon Master Gardener

    Good morning,

    Up here on the Pacific northwest coast of Oregon, we've (I guess I should only talk about myself so, "i've") been having problems this year with Powdery Mildew appearing on the leaves of some plants in ther veg tent.

    I'm considering getting a dehumidifier for use on the days we get heavy rain (almost all the time it seems) and for water/feed days when that much more humidity is added to an already humidity laidened enviroment.

    Its hard bringing in fresh air that has a high precentage of moisture in it only to add that high precentage to an already high precentaged room that just been fed or watered. Even the oscillating fans can't keep up and pushing moisture laidened air out into an already moisture laidened world doesn't seem to help.

    Rather then spray treating for bugs, I spray treat for PM now - I gotta say, i'd much rather not spray for anything but, PM seems alot less problematic then Spider Mites.

    When I get around to purchasing the dehumidifier, where would be the best place to set it up at -
    1. in the tent with the most problems or 2. in the room the tents reside in?

    The reason I ask, is becuase I have a friend who just purchased one because he's decided to move from soil to hydro and has placed a 30 pint humidifier in the back corner of the tent he grows within. From the get go, I feel as if dehumidifying a hydro grow a waste of time due to the copius amounts of water already in the room. But, I lack experience as a hydro grower or one whos ever used a dehumidifier for anything.

    AC units are just too expensive to invest in, be it there initial cost or the operating costs and being life here on the pac nw coast is mostly moist year round except those two or three weeks in August :lol:, when we have the height of our summer, I would think any unit that'll remove moisture from the air wouldn't last very long. Overly worked.

    Well, good luck retired? with whichever way you go and hope your summer arrives quickly - its suppose to be a nice weekend lots of sunshine for a change.

    Have a Great day
    STAN-THE-MAN likes this.
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    70% RH out side, 20 minutes of sun today:toast:. I will be moving soon to the east side. They have seen the sun over there for the past few months. I'm sick of living in the shadows, 2 months of summer sucks.

    Before, when I was doing Hydro (DWC) High Humidity was not the problem, low was. In my experience doing hydro, the water is contained and sealed in the system itself, not affecting the ambient air RH. I also had the main tank and pump outside the grow area.

    I have used a dehumidifier and placement in the room was all that was needed, didn't really matter where.

    Thanks don, nice to know I'm not the only one fighting powder mold. as soon as the lights come back on I'm going to give wiping the leaves off and work on the humidity. Ill have to search the net for the anti-rain dance :D:rain::dance::banana::woohoo::rofl: .

    CamperDon likes this.
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    crying2grow perfect specimen

    There are also several ways to lower humidity level without hurting the pocketbook:

    1. Spread large bowls/pots of rock salt around your grow room. Rock salt is great at removing moisture from the air.

    2. Remove anything in the grow room that is fabric or cushioned. (Towels, throw rugs, padded chairs, curtains, etc.) These type materials will absorb and contain moisture, increasing humidity level.

    3. Do not foliar feed! This is notorious for raising humidity level in grow room.

    4. Cut out circles with a "half slit" from a non-porous material that you can cover the tops of your plant containers with (especially after just watering) so the surface layer of water will not evaporate into the air, increasing humidity. Just leave a small margin around the base of the stem.

    5. Try not to talk a lot to the plants because the condensation from your breath will also raise humidity level. Use a radio, with the volume set low instead.

    6. Vacuum and wipe dry entire grow room frequently (floor, walls, ceiling and containers) because this will eliminate any microscopic water droplets and/or condensation, aiding in the goal of a lower RH grow room.

    7. Always keep your grow room as windy as the beach . . . or Chicago. lol

    The above suggestions may sound a bit redundant but if you combine these little things, you'll be surprised at how far your RH meter will go down! :2cents:

    Good luck!
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    CamperDon Master Gardener

    Good morning,

    First off ... Happy Fathers Day!

    So, its raining here again today - it began last night, a misty rain. The clouds moved in yesterday off the coast (i'm about 5 miles east of the ocean, its on the other side of Cape Meares Mountain, that I can see from my kitchen window) bringing light misty rain for Fathers Day. Yippy!

    On days like today, I wonder where the humidity in the room goes when theres so much of it all around. Does it leave the one room grow op faster then it returns. hmm ..

    Have a Great day and don't forget to call/go see your Dad
  8. Offline, go buy a used dehumidifier off of craig's list you'll make more than your money back on your crop. You get out what you put in.
    Maple3121 likes this.
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