Temperature and Humidity

Prodigus

Well-Known Member
Ok yea, noob here. I'm trying to get all this stuff dialed in and temp and humidity seem to actually be the most work.

Initially in my tent, all was well in the world but I needed a little more humidity to keep it in the 65-70% humidity and near 80 for temperature. The main challenge there after I added the cool mist humidifier was keeping the temp UP. If it was low then I'd turn my inline fan down. This would then result in higher temp but my humidity would sometimes also rise along with it. Then I'd turn the humidifier completely off and all would be ok... until the lights went out. As it got cooler overnight, the humidity would rise and freak me out when I'd wake up to 72%.

Now that everything is getting bigger and bushier, I seem to be having the opposite problem where I really don't want 65-70 anymore. I'm 4 weeks into Veg and I was thinking more like around 60% would be more appropriate (could be wrong) but with all that green and in their new 5 gallon pots, the humidity really wants to stay up there no matter what. SO, I went out and bough a 35 pint dehumidifier today and have now set that up in my room whos air feeds the tent as I don't have room in a 3x3 for 3 plants a humidifier, fans AND this fairly large dehumidifier. Now I'm playing with how low ddo I need to take it in the room so that the TENT will have the right humidity.

Am I overcomplicating this? I've read a lot of guides but I don't think I've seen any that really get into the "details" of HOW to manage these things such as adjusting fans, inlines, humidifiers, dehumidifiers etc., They just say use this for this and this for that. Anyone know of any guides or is this just a dive into the deep end and swim kind of things?

THanks!
 

FirstCavApache64

Well-Known Member
I run a humidifier during lights on most of the year depending on the humidity in the house but I usually have it on and just outside of the passive intake on my tent and set at about 5-15% above what the humidity goal is for my tents VPD. When I close up my tent and grow room for the night at lights out I turn it off and turn on my big dehumidifier that's also outside the tent and set that for about 10% less than what I want in the tent. Those numbers are what I've come up with from years of tinkering and observing the room and tent temps and humidity. I use the extraction fan speed and in room AC flue being open or closed to make any drastic changes due to fluctuating weather conditions That's just what works in my little room of 12x14 feet. I intake air right from the room and exhaust it down the hall about 25' away into the house. Hope this gives you a starting point at least.
 

hotrodharley

Well-Known Member
First don’t worry about the humidity as much as preventing molds, especially powdery mildew, during veg. Suggest a preventative spray program. However you’re right to be concerned so you can be ready for flower. Aim for 50% and late in flower for 40%-45% late flower.
 

GroBud

Well-Known Member
My plants grow in this outside, I'll try to keep tents at 40 to 50% I've found anything above 30-35% not all but most strains do fine. Lower than that most do fine just may have some dry leaves, generally older fans. As a beginner I used a ink bird for humidity before I found what worked in my environment, now the ink bird helps cut humidity on and off in drying tent. The only time I try to keep humidity up like 70% is germination and newly sprout for about a week. I do that using a dome, and all that only because my RH is so low. Seeds would sprout good without all that I just do to increase success rate. Also depending on light strength using a dome past seeds sprouting can cause dampening off, I veg under florescent or blurple so mine do fine. I wouldn't start seeds like that under a quality light. A ink bird you could plug humidifier and dehumidifier up to they would only run when needed one or the other
 

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FirstCavApache64

Well-Known Member
Also doing a light defoliation of the undergrowth of your girls will help with the humidity and airflow. That will help cut down on the chances of mold and mildews showing up as well. Airflow in the tent is important when you are having humidity that high for sure. I've never had PM indoors thankfully, but I do end up with some windburn on my lower buds almost every run so I know I tend to overdo the airflow under my canopy. I check for nanners constantly from the extra stress but I've been lucky.
 

Prodigus

Well-Known Member
Thanks! I am planning on doing some defoliation along with last topping and some serious training this weekend. So far, I see that if I want it to be around 60% inside the tent then using the dehumidifier outside the tent at 45% gets it real close. So, I guess like was stated, I just need to keep track of the moves I make and how they affect things so that I end up in the end know exactly how to manipulate my environment.
 

Prodigus

Well-Known Member
My plants grow in this outside, I'll try to keep tents at 40 to 50% I've found anything above 30-35% not all but most strains do fine. Lower than that most do fine just may have some dry leaves, generally older fans. As a beginner I used a ink bird for humidity before I found what worked in my environment, now the ink bird helps cut humidity on and off in drying tent. The only time I try to keep humidity up like 70% is germination and newly sprout for about a week. I do that using a dome, and all that only because my RH is so low. Seeds would sprout good without all that I just do to increase success rate. Also depending on light strength using a dome past seeds sprouting can cause dampening off, I veg under florescent or blurple so mine do fine. I wouldn't start seeds like that under a quality light. A ink bird you could plug humidifier and dehumidifier up to they would only run when needed one or the other
7%????? Holy Mother of GOD! I don't know why but all I can think of is how many door knobs I'd be shocked by with that low of humidity! LOL
 

Prodigus

Well-Known Member
First don’t worry about the humidity as much as preventing molds, especially powdery mildew, during veg. Suggest a preventative spray program. However you’re right to be concerned so you can be ready for flower. Aim for 50% and late in flower for 40%-45% late flower.
Do you have a recommended preventative spray? I think I'm going to be able to control it pretty good once I get the hang of it but my Son has liver disease (can never drink so he smokes) and I know the transplant team always harps about how if weed has mold in it then it can cause some horrible infection or something.
 

GroBud

Well-Known Member
7%????? Holy Mother of GOD! I don't know why but all I can think of is how many door knobs I'd be shocked by with that low of humidity! LOL
Even washing your hands you can be shocked lol crazy shit doesn't happen often js I understand what youre saying. Really hurts when the light switch hits you lol
 

FirstCavApache64

Well-Known Member
Do you have a recommended preventative spray? I think I'm going to be able to control it pretty good once I get the hang of it but my Son has liver disease (can never drink so he smokes) and I know the transplant team always harps about how if weed has mold in it then it can cause some horrible infection or something.
You want to look up bud washing for sure then to kill any active mold spores and try to get as clean of a medicine as possible. Just Google bud washing and check out a couple different methods. Doc Buds has a good one online. Also if his illness is that serious, I'd have my weed tested for contaminants after harvest. It's not that expensive and for peace of mind it would be worth it.
 

Prodigus

Well-Known Member
Down to 57 at this point now that I've been running this dehumidifier outside the tent for a several hours now. So, now I'm out of my concerned phase. Now, I'm moving into mad scientist phase and want too plan everything. Yes, I am very much ADHD.. LOL If I'm 4 weeks into veg and will probably go closer to 7-8 weeks, I'll start dropping it by maybe 5% each week before dropping it into 40's for flower? That seem bout right? And in second half of flower, I want to try to drop temperature as much as I can during dark 12?
 

hotrodharley

Well-Known Member
Do you have a recommended preventative spray? I think I'm going to be able to control it pretty good once I get the hang of it but my Son has liver disease (can never drink so he smokes) and I know the transplant team always harps about how if weed has mold in it then it can cause some horrible infection or something.
Cheap citric acid. Buy it in bulk on Amazon. 2-3 teaspoons in a quart of water and I add a couple of drops of liquid soap in after it’s mixed. Helps break surface tension on the leaf. Got turned on to this by @xtsho after spending $48 on Flying Skull Nuke Em. Shit is citric acid. It worked so I’m not bitching. But this year I’ve already started.
 

Boatguy

Well-Known Member
Down to 57 at this point now that I've been running this dehumidifier outside the tent for a several hours now. So, now I'm out of my concerned phase. Now, I'm moving into mad scientist phase and want too plan everything. Yes, I am very much ADHD.. LOL If I'm 4 weeks into veg and will probably go closer to 7-8 weeks, I'll start dropping it by maybe 5% each week before dropping it into 40's for flower? That seem bout right? And in second half of flower, I want to try to drop temperature as much as I can during dark 12?
Try not to do so much.
Your 4 week old plants in a 3x3 tent are effecting your humidity to the point of needing a dehumidifier.
Are you using an exhaust?
 

Prodigus

Well-Known Member
Try not to do so much.
Your 4 week old plants in a 3x3 tent are effecting your humidity to the point of needing a dehumidifier.
Are you using an exhaust?
Yes, I have an AC Infinity 6" inline exhausting. There's the passive hole at the bottom that is acting as an intake and I have 2 AC Infinity small circulation fans. I keep one on it's lowest setting (1 out of 10 levels) that barely goes across the top and the other one I have also pretty low (maybe 3) that passes air under the canopy best I can right now. I have a (now unused) humidifier inside the tent and now I've added the 35 pint humidifier outside the tent in my office. I don't have room inside the tent for the dehumidifier and definitely won't after I start training. Already feeling like once I start spreading them out horizontally to make my canopy even that 3 plants ion this 3x3 might be a challenge but one I'm going to take on. This morning I see that I'm running at about 82 degrees and 57%. They don't look unhappy so just gonna let them run. I had some issues last week while I was away where they ran out of nutrients and started catabolizing the lower leaves pretty good. Transplanted them into their final 5 gallon bags with a mixture of Ocean Forest (3 parts), Happy Frog (2 parts) and Perlite (1 part). They seem much happier now..
 

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GroBud

Well-Known Member
Bruh create your own thread. Dont take up other people's post with your plants unless asked to. Hes opened this thread for help not to see your plants. We all enjoy looking at plants just cant flood other people's threads with needless pics. With that said looking good bud
 
Bruh create your own thread. Dont take up other people's post with your plants unless asked to. Hes opened this thread for help not to see your plants. We all enjoy looking at plants just cant flood other people's threads with needless pics. With that said looking good bud
I was just posting how my plants are doing without a humidifier bro...my tent averages humidity levels from 58%-65% and I just have a 3 gallon fridge water dispenser opened in the tank to keep it somewhat consistent
 

xtsho

Well-Known Member
I was just posting how my plants are doing without a humidifier bro...my tent averages humidity levels from 58%-65% and I just have a 3 gallon fridge water dispenser opened in the tank to keep it somewhat consistent
Why photobomb the same photos?
 
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