Can't lower humidity below 78%. Now what?

[nice fella]

Why's everyone do worried about the humidity when he says the temperature is 68? I mean, worry about the humidity but how are you going to grow anything at 68 degrees? Maybe I'm missing something. Cold, damp, dank basements are bad places to grow. Especially if it's an old house. Lots of fungi lurking, just waiting for something nice to eat.

That never occurred to me. Ooops.

lol FML, honestly.

 

[Mr. J]

That never occurred to me. Ooops.

lol FML, honestly.

Don't take it too hard buddy!!! Nothing that can't be solved I'm sure.

 

[nice fella]

Don't take it too hard buddy!!! Nothing that can't be solved I'm sure.

Meh not by me. I'm not good at this kinda thing. Wish I hadn't dropped 2k into the grow but oh well.

There are so many variables I just didn't think of.

I think I should probably cut my losses now before I spend another 500/1k on random shit only to find it doesn't solve anything, etc.

I can justify 300 bucks on a good dehumidifier, but now apparently I need some kind of heater running down there too? So now we're talking another few hundred bucks, and another 20 bucks a month probably in electricity?

Yeah..fuck this. I tried, haha.

Anyone want an unused ROI e680 for 600+shipping?

 

[Mr. J]

Is it possible to bring air into the tent from outside of the basement? Like by attaching some ducting to the intake? Somewhere drier and maybe a bit warmer? That way the environment in the tent will be sealed off from the basement, mostly at least.

 

[nice fella]

Is it possible to bring air into the tent from outside of the basement? Like by attaching some ducting to the intake? Somewhere drier and maybe a bit warmer? That way the environment in the tent will be sealed off from the basement, mostly at least.

Not that I could realistically (safely) pull off. I live in a very humid climate so outdoor air is no help. I have no idea how I'd go about getting air in from the upstairs "house"...I'd fuck it up and do something dangerous.

 

[Mr. J]

Simply raising the temperature will lower relative humidity, and by the sounds of it you're going to need to do that anyway. I don't know man, that's all I got.

 

[Dirtyeyeball]

Buy a quest or suffer bud rot to the high humidity
Bud = humidity

 

[OG_NoMan]

https://www.icmag.com/ic/showthread.php?t=300255



View Image


.
.
.
.
.

While your numbers are great for plants they are terrible for the house with out proper vapor barriers. Your thread is among a few that I used to research before starting to grow. Thanks for your experience and info

 

[JKD]

While your numbers are great for plants they are terrible for the house with out proper vapor barriers. Your thread is among a few that I used to research before starting to grow. Thanks for your experience and info

Hi OG,

That thread belongs to DJM or Don Juan Matus,

I can't claim credit for it, but appreciate the sentiment.


All the best
.
.
.
.
.

 

[OG_NoMan]

Meh not by me. I'm not good at this kinda thing. Wish I hadn't dropped 2k into the grow but oh well.

There are so many variables I just didn't think of.

I think I should probably cut my losses now before I spend another 500/1k on random shit only to find it doesn't solve anything, etc.

I can justify 300 bucks on a good dehumidifier, but now apparently I need some kind of heater running down there too? So now we're talking another few hundred bucks, and another 20 bucks a month probably in electricity?

Yeah..fuck this. I tried, haha.

Anyone want an unused ROI e680 for 600+shipping?

The dehumidifier will add heat to lower humidity and then your going to have to cool the air as it gets to hot. An AC is more efficient in removing humidity but when it isn't cooling it isn't removing humidity. It's like chasing your tail while throwing money. If you're not handy this isn't necessarily the best hobby as it can get very expensive indoor. Also as someone else stated in this thread, you want to treat the basements air because the tent is pulling air from the basement. If going the route of hepa filtration your filters should be on the tent intakes. Also keep in mind that there are many ways to skin a cat

 

[nice fella]

Thank you. The little in-tent dehumidifier is not lowering temperatures at all (as you'd expect).

Now that I've calmed down and stopped feeling sorry for myself...maybe, in these hot, humid summers I can just open a windows or two in the basement to get temperatures up in the 70's. Then couple that with a big-ass dehumidifier and co2 bags?

Also maybe stick to autoflowers on 20/4 or 24/7 would keep the temps up.

 

[dramamine]

Dude, I would say get an HPS light in there instead of LED. It'll bring your tent temps up and lower humidity somewhat too. You could run the LED if seasonal temps go back up.

 

[Mr. J]

Dude, I would say get an HPS light in there instead of LED. It'll bring your tent temps up and lower humidity somewhat too. You could run the LED if seasonal temps go back up.

Honestly I don't know why I didn't think of that. Best advice in this thread. 1000 watt HPS is your best bet right now.

 

[Chevy cHaze]

Here's a quick fix that I have been using in very humid but brisk environment in the northern UK with success.
First step is to check what air intakes your tent has.
My Secret Jardin lodge tent has mesh panels with velcro cover flaps on each side.

I have the dehuey outside of the tent and have it blowing exactly into that mesh screen.
You'll never be able to bring the rh in the whole basement down at once, but this way all the air going into the tent is dry. And also this air is normally a bit warm, so that solves your problem with the low temps.
If your tent architecture is different you might have to MacGyver something, but just make sure the dry, warm exhaust air from the dehuey gets into your tent somehow.
It will be more efficient than running the dehuey inside, as when you do that, the humid air from the outside first has to mix with the exhaust air inside the tent rather than ALL the air getting sucked into the tent already being dry and warm.
Best of luck and be aware mold is real

CC

 

[Dion]

Here's a quick fix that I have been using in very humid but brisk environment in the northern UK with success.
First step is to check what air intakes your tent has.
My Secret Jardin lodge tent has mesh panels with velcro cover flaps on each side.

I have the dehuey outside of the tent and have it blowing exactly into that mesh screen.
You'll never be able to bring the rh in the whole basement down at once, but this way all the air going into the tent is dry. And also this air is normally a bit warm, so that solves your problem with the low temps.
If your tent architecture is different you might have to MacGyver something, but just make sure the dry, warm exhaust air from the dehuey gets into your tent somehow.
It will be more efficient than running the dehuey inside, as when you do that, the humid air from the outside first has to mix with the exhaust air inside the tent rather than ALL the air getting sucked into the tent already being dry and warm.
Best of luck and be aware mold is real

CC

fuck yeah to that

the rice bags and dehumidifying shit wont work as chevy said

in my experience its like trying to dry clothes under water, u cant do it so for sure dont try dry the air, just send the dry air right in makes soooo much sence


and also the HPS is good for heating and drying, im an led guy but i used to have 250w of hps in the room during winter when i lived in europe...hps is a great heater for sure

 

[Switcher56]

The info provided in the original post was sporadic at best, a common mistake folks make when asking for troubleshooting help. So, I decided to go back to the beginning and see if we can't help you out here, from the additional data.


(click to enlarge)

The optimum growing temperature is 20-25 deg C or 68-77/78 deg F. Your humidity should fall within the guidelines of the (Vapour Pressure Deficit) chart.

So I'm growing in a 4x4 grow tent within a humid (but temperature controlled) basement. FWIW, it's also 90% humidity outside right now.

As I. I grow in my basement. in a 10x10" room. The only equipment in my tent (outside of the light and exhaust fan) is a misting humidifier, controlled via an Inkbird controller. The same controller will kick in if RH becomes too high. You can also control the amount of RH by adjusting the speed of your exhaust fan. Adjust = tweaking! As you increase the volume of air exhausted, the RH will decrease but also your temps. Hence the word tweaking. You can only tweak so much.

I ordered a recommended dehumidifier and ran it inside the tent, with passive air intake and the a 435cfm inline fan running for 24 hours. 78% humidity.

Dehumidifiers will raise air temps by 6-8 deg F, not desirable during the summer months. Therefore, originally I had the suction at the top of the tent and the return at the bottom. That was simply not suitable. I still suck from the top but, discharge outside the tent via a charcoal filter which sits on top of the tent. Problem solved!

BY having your dehuey in the tent, you are sucking air from your basement (read uncontrolled environment) My set up...


(click to enlarge)
Pic 1 shows dehuey and radiant htr (left). Right hose = suction (top of tent). Pic 2 shows charcoal filter on top of tent (discharge)

I then shut off the inline fan, kept the passive air intake vents open/dehu running and waited 24 hours. 78% humidity.

Never turn your fan completely off, it needs to recirculate/exchange the air. Running @78% RH and 68 deg F, is asking for trouble. Check the VPD chart out. You are in the danger zone. Keep it in the green.

What can I do here? The basement is like 900 square feet so...just buy 10 more dehumidifiers? Move the grow upstairs? Will Co2 bags solve the problem? Thank you.

Relax You are flying from the seat of your pants.

This is 78 percent humidity without the light even running yet.

I'll be running an LED light, specifically the Growers Choice ROI e680.

... as temperature rises, RH decreases and vice versa.

Well, the heat pump (air conditioner) is in the basement and it leaks a little so I sorta have half-assed AC down there. Right now it's 66 degrees F.

2 things wrong here. 1 you got a leaky AC = adds humidity and 2, your basement temp should be 68-70 deg, no lower. You need to control the environment.

I have a few small oscillating fans running in the tent.

IMMHO, they don't do shit, with the exception of circulating air to distribute RH and temp evenly throughout the tent and, makes stronger stalks.

I'm thinking keep the small dehu in the tent. Get a big ass fancy dehu for the rest of the basement, and open doors as needed for airflow as the grow progresses?

Your AC is a dehumidifier of sorts, don't go there yet. Read my post #15. Because of our large temp?RH swings during the summer here in the Maritimes. I no longer grow during Jun to end Aug. I don't need to run my tent during the summer to see to "my" needs and simply don't want the hassle (e.g constantly tweaking my environment) and expense, not to mention taking the summer off.

Meh not by me. I'm not good at this kinda thing. Wish I hadn't dropped 2k into the grow but oh well.

There are so many variables I just didn't think of.

I think I should probably cut my losses now before I spend another 500/1k on random shit only to find it doesn't solve anything, etc.

Not necessary! From your own admissions you winging it! Not all is lost here. You need to think things through and, perhaps we might be able to offer assistance. That being said... one size doesn't fit all

I can justify 300 bucks on a good dehumidifier, but now apparently I need some kind of heater running down there too? So now we're talking another few hundred bucks, and another 20 bucks a month probably in electricity?

Why are you running an AC then?

Yeah..fuck this. I tried, haha.

Wrong defeatist attitude my friend. What literature if any are you in possession wrt growing cannabis?

Anyone want an unused ROI e680 for 600+shipping?

ROs are overrated. Unless your water supply is bad, there is no need for an RO system. Most problems occur with improper PH swings, and, at times have nothing to do with the water supply but the grower. I've been growing going on 2 years and have no use for one. My 1st grow was successful but I had issues. Wrong nutes and didn't know about VPD. Corrected my VPD and woila. I still had issues (nutes) due to improper soil PH. I was advised I didn't need to worry about PH with the nutes I was using (GO) Changed my nutes to Remo and now monitor my PH diligently, always providing a PH swing. IOW, I never use a set number what a difference that made. No more issues!

Not that I could realistically (safely) pull off. I live in a very humid climate so outdoor air is no help. I have no idea how I'd go about getting air in from the upstairs "house"...I'd fuck it up and do something dangerous.

Again, why are you runnign an AC in your basement? What is your living condition like upstairs? BTW, it is against "fire code" to pierce floors etc... (fire spread). It is here anyway.

Thank you. The little in-tent dehumidifier is not lowering temperatures at all (as you'd expect).

Previously answered. It is your exhaust fan and ambient temps that will do the job for you.

Now that I've calmed down and stopped feeling sorry for myself...maybe, in these hot, humid summers I can just open a windows or two in the basement to get temperatures up in the 70's. Then couple that with a big-ass dehumidifier and co2 bags?

Maybe I'm not reading your question correctly. Please explain your rationale for using CO2 bags?

Also maybe stick to autoflowers on 20/4 or 24/7 would keep the temps up.

Personally I don't like autos. They are more expensive to grow and the yield doesn't justify the expense. Furthermore, it won't help solve "your" problem.

My set up...

Veg tent

• 2x2x3'
• 300W lead
• small tower circ fan. In corner of tent oscillating for a 90 deg sweep.
• 190cfm variable speed fan and charcoal filter.
• Misting humidifier
• Inkbird controller (RH)

My main tent

• 3x3x6'
• 600W LED
• 2 circ fans installed to bounce off side wall. One at back of tent, the other at the front of tent. One set 1/3 down from the ceiling, the other 2/3 down. Both at an angle but not blowing directly on the plants. They have 3 speed settings and I run them on 1
• 4 in 190cfm variable speed fan and charcoal filter.
• Misting humidifier
• dehumidifier (outside tent)
• Inkbird controller (RH) and temp controller
• Radiant heater (outside tent (winter))
• Window AC supplies cooling warmer months for the basement.
• Both tents have recycled light grids for flooring

Basement

• humidifier (winter)
• dehumidifier (summer)

The aforementioned items are part of living here in the maritimes. We play the cards we are dealt. Ya gotta be smarter than the dealer. I hope this helps. Like "Smokey" used to say... "Only you can prevents forest fires" You must control your environment. I hope this helps

 

[nice fella]

Just wanted to thank everyone for your very kind advice and give an update.

I have an electrician coming over tomorrow to build a dedicated 20 amp outlet in a spare bedroom. I've ditched the basement idea due to the unforeseen, aforementioned temperature issues.

I will still have humidity issues but I think they will be easily mitigated with temperature control (central ac/heat) and a good dehu (for now, at 72%F, a 50 dollar ebay special dehu dropped the room from 81% into the high 50's!).

I wasted a lot of money and effort on the basement grow so I was...a bit too dramatic in learning that it wasn't the way to go.

Moving forward..

 

[roybart]

I have the reverse problem. Too dry 25%

I have plenty of airflow as the room has a 6 inch duct which goes to a 6 inch inline fan under the floor and then piped 20 feet away from the room. I have 2 small fans to make the girls sway.
I am a little limited with A/C so I can only keep it to 90 ambient but that only for about 3 hours before and after that its 85 ish room temp depending on the day and time.

I have added ice to the tops of my buckets so that should help a little.This is for the really hot days like today

Yesterday it was 116 today 112 but it will return back to 105's tomorrow.
I can add more A/C but then the humidity will be even lower.

When its 105 ish the top room temp is about 85 and it drops to maybe 80..
I need to get a humidifier..
https://www.generalfilters.com/support/humidity-calculator.html tells me that I need .62 gallons / day
I found a humidifier on craigslist for $12 which does 1.2 gallons per day.
I think I might be Ok just maybe the humidity my help cool it a bit?

Thanks everyone for the advice on this thread.

 

[Peacefrog]

I have the reverse problem. Too dry 25%

I have plenty of airflow as the room has a 6 inch duct which goes to a 6 inch inline fan under the floor and then piped 20 feet away from the room.

Your problem is that you are sucking air out of the room and bringing in more hot dry air. Your plants will raise the humidity in the room if you keep them watered and just cool and recirculate the air within the room and don't exhaust it - assuming you can use a room AC and not central air. Eventually during flowering if you recirculate air you may actually have to run a dehumidifier if your AC can't keep it down.


And run your lights at night when the ambient temperature is lower if you aren't doing that already.

 

[roybart]

Your problem is that you are sucking air out of the room and bringing in more hot dry air. Your plants will raise the humidity in the room if you keep them watered and just cool and recirculate the air within the room and don't exhaust it - assuming you can use a room AC and not central air. Eventually during flowering if you recirculate air you may actually have to run a dehumidifier if your AC can't keep it down.
I have shut down the 6 inch fan already. My AC source is from the house and the grow room is attached to the house. So its a balancing act trying to keep it humid and cool. I got a https://aircareproducts.com/hd1407.html for $50 US on Craigslist. It was like brand new. Setting it to 65% Humidity is working so far. Still playing with air management within the space..



And run your lights at night when the ambient temperature is lower if you aren't doing that already.

My electric does not have any off peak rates. I run 12/12 so running the lights during the day is better for me. Also I am kinda semi retired so its important to keep girl work during the day. I don't know what would happen if I were to switch the schedule how traumatic that would be. It looks like its 24 hours of darkness then switch to new schedule. That being the case, i will research it more and maybe do it. In a month temps will be easier to manage.
In the winter I can leverage the LED heat(not much) and steal heat from the house just like I am stealing AC at the moment.

Thanks for the input..