Humidity & Temp?

siforek

Member
Thus is my 1st grow. I've been slowly purchasing equipment & nutrients as I needed/could afford them. I'm about 4 weeks into veg in a 2x4x5 tent & my plants are looking great!

While I've been controlling the temperature with a greenhouse thermostat outlet & a small heater I just got a digital thermostat/humodity sensor last week at which point I realized my tent was at 70% humidity, a little high but figuted it'd be ok. I removed a bowl of water & rag I had hanging in it to increase humodity & figured I'd be fine.

The next day & ever since it's been raining here in norcal like crazy & with my tent outside on my porch that's definitely a big contributor to the now 85% humidity in my tent :/

I went to my local grow shop yesterday & afyer looking at recent pics of my plants they identified a little powdery mildew one 1 & gave me something to mix/spray on them. Problem is that increases the humidity even more for a while.

I was planning on just getting a small $30 dehumidifier off Amazon but before I do do you think removing 8oz of water a day will be enough to get it dosn to 60%?

Also while I've read you want temperature to drop about 10 degrees at night mine doesn't. It's constantly at 73 degrees. Is that ok or should I spend the $50 on another thermostat outlet that will allow me to set a slightly colder night temperature?
 

chemphlegm

Well-Known Member
73 all day and night is good.
you could raise the temps a bit to help
buy a real dehumidifier or smoke mold
 

siforek

Member
Raise the temperature to help what? That would make it more humid right? I need a small one that's not going to take up too much space in my tent unless there's something that can pull through a 4 inch hose ported out the tent?

What's smoke mold?
 

chemphlegm

Well-Known Member
high humidity will allow mold to flourish. If you keep doin what you're doing you will be harvesting moldy plants, then considering smoking them too=smoking mold
you tell me, raise the temps in your space, stop the dumb wet rag and see the difference. I read that in a grow bible.
your plant will grow to its weakest resource. whatever that is, thats what you get. if your expectations are low maybe a tiny dehuey will work for you. keep an eye on your humidity. I have one that records highs and lows day and night for me to review.
 

MissyGoddess

Well-Known Member
I am just as new as you so I don't have really much advice to offer, just some thoughts. Being outside it seems almost impossible to control temp and humidity in a tent. I have bought those little Dehumidifiers off of Amazon and from my experience, they will not put a dent in humidity in your circumstance. It will just be throwing money away. I just bought a $250 70pint Dehumidifier for my grow tents that are in a garage because the 50pint one I bought can't keep up with it raining outside. On dry days I can get it down to 30%, but wet days it struggles to keep it below 50% which is why I went bigger. My 2 tents are a 2x4 and a 4x8 inside a 2 car garage.
 

siforek

Member
Oh I got ya! I stopped the wet rag thing 1st thing last week & definitely need to drop the humidity asap. Normally after feeding them I see a huge increase in growth the next few days but not this last time & I'm assuming it's due to tge humidity & my plants taking up far less water from their leaves
 

siforek

Member
I am just as new as you so I don't have really much advice to offer, just some thoughts. Being outside it seems almost impossible to control temp and humidity in a tent. I have bought those little Dehumidifiers off of Amazon and from my experience, they will not put a dent in humidity in your circumstance. It will just be throwing money away. I just bought a $250 70pint Dehumidifier for my grow tents that are in a garage because the 50pint one I bought can't keep up with it raining outside. On dry days I can get it down to 30%, but wet days it struggles to keep it below 50% which is why I went bigger. My 2 tents are a 2x4 and a 4x8 inside a 2 car garage.
Shit that's what I'm worried about :/ In veg they'll be more forgiving but I'm not doing all this work for moldy buds. While I'm sure the rain is the main cause & once it stops it'll go back down to around 70% that's still high for veg & even if a little dehumidifier could get it to 60% now my plants are just going to get bigger & sweat more so...

I think I might be able to get away with a small cheap dehumidifier right now but once I switch to flower I need an affordable way to keep my humidity way down to 40-50%.

If a 10x more expensive dehumidifier really is the only option I have no choice & will end up forking over the dough BUT can you suggest any that are more designed to be ported into it so it doesn't take up half the space in my tent?? I could get all MacGyver on it of I have to & make my own way to port it in but...

Also I've recently been looking at some of those heater/ac + de/humidifier combos. My thoughts are that in summer I may need to cool the tent too so if I'm gling to spend the $ I may as well get everything I'll ever need on that front.
 

siforek

Member
Looking at some larger dehumidifiers on craigslist etc. Ones that can remove 5+ gallons of water a day would probably be more than enough, problem is they are far too big to place inside my tent. I'm considering possibly taping up & ducting the in/out vents into the tent so I can place it just outside of it. Thoughts/suggestions?
 

MissyGoddess

Well-Known Member
I don't know of any personal sized dehumidifier that is capable of being ducted. They make house ones that go inline of your home HVAC but cost $1000+ and not at all meant for what we need it for, small tents. Question, is it possible to somehow duct air in and out of the house to the tent on the patio? That would at least help the situation for very little money if you can someone tap into the house (ie. drill big holes and call them 'dryer vents' LOL). I had a friend do it that way but it was from the back of his garage to his backyard, not a big deal to him (his wife thought differently though). It isn't a real fix to the problem but I can only imagine it helping with keeping temps and humidity a little more stable and closer to proper ranges.
 

siforek

Member
Yeah that's a no go. I live in an apartment right now :/ I will be moving in June at which point my tent will be in the garage which will solve most if not all of these issues. That's also why I don't really want to spent a ton of $ on all this stuff if once I move I never need to use it again.

We're only talking about 8 square feet! I'm not sure exactly how much more humidity double the plant matter would produce/sweat but lets assume it's not raining like crazy 2 months from now, it'd probably keep around 70-75% humidity. So to bring 8 square feet down to 40-50% how much water would need to be removed per day?
 

MissyGoddess

Well-Known Member
I am removing about 5g a day in my garage and I am losing the battle. Humidity is hovering around 45 but the heat from running the 750w dehumidifier non stop has got the garage and tents up to 83 today. :(

The problem with a tent outside is it isnt completely sealed so a small dehumidifier will be fighting mother nature, not just the inside of the tent. That's just my thinking and I could certainly be wrong.
 

siforek

Member
When it's raining like crazy & outside humidity is upwards of 90%+ I wouldn't expect a small dehumidifier to help much. As you said it's not completely sealed so...

On that note I was thinking about covering the ouside of my tent in that waterproofing stuff you just paint on. You kniw the stuff where in the commercial they install a screen door on the bottom of a boat, cover the screen in that shit & take it out on the lake w/o any leaks? Lol anyway I'd assume a better seal would be good for more than just humidity. CO2 in particular.

Anyway I just received a small dehumidifier I o4dered off Amazon. I literally spent 6+ hours the last few days researching all kinds of options & using various online calculators I figured if the humidity were to stay this way I'd need something that could pull a pint of water out of the air every day. Assuming once it stops raining so much I'd need to remove far less I found a decent priced/sized dehumidifier that can almost remove a pint/day. It's been running now about an hour & already dropped humidity 5%. But I'm crossing my fingers & keeping the box in case it doesn't pan out.

I did seriously consider a larger one, like those 30-70 pint units that new are about $170+ & figuring out a way to duct the in/outs to the tent while it sits outside of it.. I may still have to do that, especially in flower since I'm not doing all this work for moldy buds :P

If I need to go that route any suggestions on a decent & affordable dehumidifier I can duct to/from the tent would be great :) Thanks!
 

siforek

Member
So after running it all yesterday & last night the little dehumidifier just isn't cutting it :/ This morning my humidity was only at like 65% & it barely had a few drops in the tank which was weird because after the first 2 hours I had it in there it had a half cup or so. Now my humidity is at 78% & it's a bright sunny day so I'm gonna assume it can only get worse.

I found a Kenmore 30 pint dehumidifier on Craigslist for $70 ($10 more than this little crappy one) so let's hope it fixes this :P

I nearly bought some Flex Seal at Home Depot last night thinking if I coated the outside of my tent it'd better keep the outside humidity from effecting the inside. I didn't because I'd like some feedback before I do & I'm also thinking that my tent seems fairly air tight where there's mylar aside from the ports & zippers.
 
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