I can’t get my humidity down in my tent I beginner that needs some help

[Craigr840]

So this is my first time growing I have two plants in a 4x4x6 tent with a carbon filter exhaust fan system with 3 dehumidifiers in there one that’s plugged in and two that are canister ones like for a gun safe and I can’t get my humidity to drop down past 60% it’s in my basement and lately it has been hot here so it has actually gone up to as high as 67% and I’m just baffled because like I said I have 3 dehumidifiers in there and it’s just not going down any suggestions? The temp is always right around 70-74 degrees and I just have 1 1000w led light in there so it’s not crazy hot

[DeadlyFruit]

I’m not sure I can help you - that situation makes no sense. When my grow room gets too humid I move my one de-humidifier into it and the humidity comes down to whatever rH I set on the de-humidifier. Are you sure it is working properly? How often do you empty it and what rH is it set for? How humid is the rest of the house? Not to ask dumb questions but I can’t think of anything else it could be.

[PLreef]

By the looks of it your still in veg. 65% - 70% is pretty good IMHO. Tad high but still ok. Once you get to flower you'll definitely need to lower it. How many sq ft is you dehumidifier rated for?

[homegrown]

I think your fighting a loosing battle if your basement(room) humidity is the problem. Your constantly sucking moist/damp air into the tent. Maybe get a bigger de-humidifier and reduce the humidity in the basement. Works well for me. plus that de-humidifier running in your tent is gonna generate some warmth running all the time.

[MagicMike66]

You’re spot on there. I had this before in my tent as well. I found a way of exhausting the hot air directly outside, now I can’t get my tent above 50% rh without adding a humidifier

[Craigr840]

There is a dehumidifier in the basement maybe I do need another one or a bigger one

[Craigr840]

I just opened the windows down there hoping that will help the air flow

[Puglover1]

Are your gun safe dehumidifiers using desiccants? Do you change or dry the beads out often? Not sure they're up to the task of removing much moisture in a tent of growing plants, in a basement.

[Craigr840]

I just got those to add to my other mini dehumidifier so with the one that plugs in and the 2 gun safe ones there is 3 inside the tent and one outside the tent

[Craigr840]

I was just thinking should I try and put up plastic in the basement to create a room where the tent is instead of trying to dehumidify the entire basement?

[DeadlyFruit]

Not sure how powerful the mini dehumidifier is but I suspect you won’t be able to seal the enclosed area well enough to keep the higher rH air out. If your tent ventilation fan vents outside it will also suck air into the enclosed space from the rest of the basement because the air going out has to be replaced from somewhere.

As I mentioned below I think your two options are to either get a better dehumidifier and lower the humidity in the basement or else lower the fan speed on your tent ventilation fan to give your mini a chance to make a dent in it and limp along this way until you either harvest or your central heat comes on and lowers the rH that way. This second option may also require you to dial down the light power if there is too much heat.

One final thought - 65% is a bit high but it isn’t automatic death for your plants. I think they would be fine in veg growth and while it could be a bigger problem for bloom it doesn’t automatically mean you would have bloom rot or some other similar problem. Plenty of people grow outdoors in places with high humidity (I’m not one of them so I can’t give advice on any special techniques but you might ask specifically for advice from growers in high humidity regions). The pic above of your plant looks like it isn’t in bloom yet so you have a little time to figure it out.

[DeadlyFruit]

I suspect your mini dehumidifier isn’t cutting it because your venting system is constantly pulling new moist air into your tent and it can’t keep up. In a pinch you might be able to slow down the fan speed pushing air out of your tent so the dehumidifier has a chance to make a little more of a dent in the rH but that isn’t a long term solution, especially if that causes the tent to heat up. If in winter you run central heating your house humidity will drop so perhaps you limp along until that comes and then in the future you either skip a summer grow or do it outside. A long term solution would be to buy a full size dehumidifier to run in the basement so the air going into your tent is lower humidity to start with and the mini can bring it down further in the tent if necessary. Not sure of your budget but these seem like your most likely options.

[55oldman420]

What I did is kinda costly but I bought a 20 pint dehumidifier for outside my tent so I can control the humidity of the new air coming into my tent.

[Helie]

I just got this to add to my other mini dehumidifier so with the one that plugs in and the 2 gun safe ones there is 3 inside the tent and one outside the tent

Who could tell me that growing is a really hard thing... actually had similar problem but I have normal size dehumidifier

[Ckbrew]

Dehumidifiers in the actual tent will not help if you have proper air exchange in the tent- all the air in the tent should be frequently changed with room air by the exhaust fan. You need to dehumidify the entire room that the tent is in. Basements usually are more humid due to being underground. Get a room dehumidifier big enough for the entire room.

[3Berries]

If you raise the temp in the tent above the room, then the RH in the tent is easier to control. And look at a Vapor Pressure Differential chart. 70% is not bad at 82F or so. Just have constant circulation in the tent.

https://vpdchart.com/#F,70,81.5,81.5,0