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Reduce humidity


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I hope this is the right place, I am just off to flip my plants to flower but my humidity is sitting at 70 and I'm trying to reduce it obviously.  The plants are very healthy but I'm not wanting to flip until I get the humidity under control. I have a small dehumidifier as it was all I could afford but wonder if I should pay out for a better one and if so do you guys have any suggestions.  Many thanks in advance! 


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3 Answers

I know one thing, the dehumidifiers that cost around 60 quid and advertise to remove half to one litre a day are a waste of time. They are shite.

I think you need to get something thats rated around 10 litres a day upwards to make a meaningful difference, using it in the room where the tent is.

There's no really easy solution to be honest, if there is moisture in the air you either need to dry it, with a dehumidifing device or replace it with drier air.

Inside our house in the UK at this time of year is around 60% upwards so it's always a bit of a struggle. Just keeping up good circulation into and out of the tent seems to be the best solution

I'm also in the UK and the humidity is really high right now.  At the moment I have a shite dehumidifier and an inline fan from the tent to a window via hosing, is it worth adding another inline fan do you think?


If the outside humidity is high, all your doing is pulling moisture in!


I think you need to control the humidity in your "lung room" which is the room your tent gets its air from or get creative. So, you can either get a larger room-sized dehumidifier and listen to it run all day and all night, or do what I do. I bought a cheap room dehumidifier (20 pints I think?), used, and placed it next to my tent. I then ran a dryer vent hose from inside the tent to the back of the machine. I duct-taped it to the back and used more tape to cover the rest of the area that vents the air out so that it will pretty much all do through the hose into the tent. Now, your issue is that it will always be running because its sensor is not inside the tent. On amazon, I bought a cheap inkbird humidity sensor/controller which basically has a sensor that goes in the tent and on the outside is the main unit and two plugs. When the humidity gets above your setting it turns on the power going to the dehumidifier and when it gets there it turns it off again. I set mine with 10% variance so to speak, so it is set to 52% but before it triggers it is 10% higher. So it comes on at 62% and stays on until it goes down to 52% and goes off. That way it is not always switching on and off. The other plug on it is to do the same with a humidifier if you so desire.

The new issue for you will be heat because the dehumidifier especially cheap ones blow out air that is hot as well as dry. I use a temperature-sensing fan that exhausts to the outdoors when it gets to a set temperature in the same way the inkbird makes the dehumidifier does. I use the AC Infinity.

I hope my explanation of how I do it is helpful to you. It does not have to be expensive, it just has to be safe and do the job. Smile

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When buying  an old used dehumidifier make sure you do not get one of the newer ones that are digital because some of them are not real friendly with being turned on and off through the plug, so get an old analog one similar to mine in the photo.

It's good to see Heath Robinson alive and well Thumbs Up  

Thanks I will see if I can do this.



If your in a tent open another flap slightly to let more air in , otherwise its a bigger extractor fan to move more air through ? Thumbs Up  

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