Humidity seems high at lights out

Discussion in 'Marijuana Plant Problems' started by Skoal, Mar 13, 2019.

  1.  
    Skoal

    Skoal Well-Known Member

    My humidity seems high when the lights are off. Humidity is at about 70-80 when dark. I run my 4 inch exhaust fan only during lights on. Humidity with lights on is usually around 40%. Should I be running my inline fan 24/7 to get rid of that humidity during the sleeping hours?

    I also just realized my circulating fan has only been running during the lights on. So that’s probably the reason as well having my air not moving when lights are out. So I’m going to run just the circulating fan at night and see if that lowers the high humidity
     
    Last edited: Mar 13, 2019
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  2.  
    3rd Monkey

    3rd Monkey Well-Known Member

    Just filling us in lol?
     
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  3.  
    Skoal

    Skoal Well-Known Member

    I’m super baked now and am basically thinking out loud. Just trying to get the concepts down in my head. Is my line of thinking correct though? Moving around that humid air when lights are off will help decrease it?
     
  4.  
    3rd Monkey

    3rd Monkey Well-Known Member

    Yea, or just the exhaust.

    Just thought it was funny because you gave the problem, how to solve it, but left it open ended lol.
     
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  5.  
    Blitz35

    Blitz35 Well-Known Member

    What are the differences between your lights on and off temps? You can try increasing the temps a bit (as long as it remains cooler than lights on by a few degrees), that would lower humidity as well, but the fan is a better first option if temps are close already.
     
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  6.  
    Lucky Luke

    Lucky Luke Well-Known Member

    Plants transpire and when the lights are out there is less evaporation.
     
  7.  
    Beachwalker

    Beachwalker Well-Known Member

    Unsure if you're talking about veg or flowering humidity, however both fans should be on 24/7 under humidity that high, good luck
     
    Last edited: Mar 14, 2019
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  8.  
    Skoal

    Skoal Well-Known Member

    Sorry guys, forgot to mention it’s under veg. As she gets larger and larger I’m noticing she transpires a lot more at lights out. Which is understandable because he is getting much bigger. Well I ran the circulating fan all night so I shall see if that lowered the humidity max. If not I’m gonna run the in-line fan as well I guess. Didn’t want to run both fans 24/7.

    Lights on the temps are about 22-25c. Humidity 40%

    Lights out, temp is about 18-21c. Humidity high hits 80%
     
  9.  
    nobighurry

    nobighurry Well-Known Member

    Buy yourself a humidistat and hook it to an inline fan, it will save you a bunch of problems present and future, it only runs the fan when the humidity gets above your set points, IMO the more automation the more stable your grow environment...
     
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  10.  
    Skoal

    Skoal Well-Known Member

    The next fan I grab for the flower tent is going to be an infinity fan. Allows you to control both humidity and temperature. Downside with the humidstst is it only does humidity. I want one to do both cause the fan needs to run when lights are on to ensure the tent doesn’t get hotter than 27. MH bulb heats like hell. Or can a humidstat kick on when both the humidity and temp get up to a certain point? Lights on I’m fine with humidity and temperature with my exhaust running. Lights out my temps go a tad lower but nothing crazy but my humidity sky rockets. I don’t wanna hook an in-line fan to a humidstat which would only kick at lights out. I need it on during lights on to control temp as well.
     
    Last edited: Mar 14, 2019
  11.  
    nobighurry

    nobighurry Well-Known Member

    Indeed I have an autopilot environmental controller does co2, temp and humidity shop around I got mine for $139.. no doubt there are other options out there.. but if you plan on staying in the game I’d pony up you will not regret it my friend
     
  12.  
    Skoal

    Skoal Well-Known Member

    Oh I intend to be in the game. I was in it back in 2008. Now with it legalized I’m back up. Any recommendation on the Ac infinity controllers? I may run one of those on my vivosun fan for the veg tent and run a full Ac infinity set up in the flower.

    Just sucks that during the day I have heat problems and night is humidity. So I’m theory I need a controller to kick on at doffeeent settings to stabilize the heat during the day and stabilize humidity at night. All this tech confuses me haha.
     
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  13.  
    jtrizzy

    jtrizzy Well-Known Member

    Or just leave your extraction fan on 24/7.....There just saved you $140. Your welcome.
     
  14.  
    athomegrowing

    athomegrowing Well-Known Member

    I don't know anyone with a tent who doesn't run their fans 24/7. This doesn't mean I want to hear from you if you don't run your fans 24/7, it means that it is unheard of.
     
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  15.  
    nobighurry

    nobighurry Well-Known Member

    I do not have any experience with infinity equipment, I am partial to hyper fans although they come with a speed controller I never adjust it she runs wide open when on, they run very efficiently saves on the power bill, I had a Big pill shaped fan, it moved over 600cfm but it was obnoxious I could hear it from 100ft away! Plus I didn’t need to move that much air, the cheap speed controller fried it in less than 8 months.. good airflow would sure help with your hot & humidity issues my ac only runs during the heat of summer and I run HPS in flower room..
     
  16.  
    Skoal

    Skoal Well-Known Member

    A fan running 24/7 on the ground lowered humidity at night to a max of 47. And it somehow increased the tent temp to 21c with lights off. Think I’m gonna try this for a bit and grab a clip on fan ive been meaning to grab. I just hate running my exhaust all night cause fuck it’s loud hearing all that sir being pushed. Fan itself is quiet. The air itself, not so much haha
     
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  17.  
    nobighurry

    nobighurry Well-Known Member

    Sounds like you need a silencer or differnt fan, my old fan made tons of rushing air noise, high speed-high pressure, current fan is very quiet I have to put my hand on it to see if it's running, I run my wall fans 24-7, you might try leaving a flap/zipper open at night but your inline will help the most to rid the humidity, not sure what your day vs night temp difference is but you will see more humidity the bigger the differance, I keep mine at no more than a 10deg differance which drastically eliminate nighttime humidity,
     
  18.  
    FastFreddi

    FastFreddi Member

  19.  
    Skoal

    Skoal Well-Known Member

    Yeah it’s a vivosun in-line 4 exhaust fan. The fan itself is damn near quiet. But the noise of the air being exhausted out of the ducting at the other end is super loud.

    But humidity seems to be dialed in at 47% at night with 21c temps. And 35-40%RH during the day and 25c for temps. So seems like it’s working for me at the moment.

    The more plants I back in there I may need to invest in a controller to kick it on when required.

    I’ve heard good things about the infinity one so that will be for my flower tent which comes with a temperature and humidity controller.
     
  20.  
    Beachwalker

    Beachwalker Well-Known Member

    Fans keep the air moving but the humidity is going to stay whatever the humidity in the ambient environment is, that is to say if it's 50% RH in the atmosphere then the best you're going to get in the tent is 50% and that's even going to be tough, fans don't do as much as I think you might be expecting them to do, as they are not dehumidifiers
     
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