importance of exhaust fan

[garybob69]

super noob here. second year of growing, sort of. just a 2'x4'x5" tent. I have a 6" exhaust fan I never used (Ipower big round and loud), vents up into the attic of my home. never seemed to need it? if their was an odor I didn't notice nor did I care. I've only been trying to grow autos, trying to diminish the hurting on my wallet going to dope dens for my medicine, plus I don't think it's all that good any ole way. I'm 65 years old and on a fixed income. So anyway I've been doing some reading, says I should use the exhaust fan to bring in fresh air for the plants to breathe and get oxygen. Okay, I don't get the best production, nothing like I see in the pics on the internet and you tube. But I'm not greedy either. So I thought I'd give it a whirl. Zipped up the tent, turned on the fan, I have it on a controller, sped it up till a tissue would stick to the carbon filter (has cover thingie over the filter) a couple minutes later my RH is down from 52 to 40% and the temps go up 2-3 degrees. I should add that I have a 6" inline fan at the bottom of my tent pulling in air. so I have to turn on the A/C, (window unit 5,000 btu) to draw down the temps., but that does nothing for the RH, plus I'm now using more electricity. I get the thing about recirculating or replacing the air in the tent. But how is the fan any better than what I was doing before. I live alone out in the country, no friends to come by so I just leave the tent flap/door open bout a third of the way, regulate temps by the a/c or closing the bedroom door or just cracking it open a bit. with the inline fan pulling in outside air, the flap being open, I have a tower fan in the tent (oscillating). Both fans run 24/7. It's getting cooler where I'm at now and would like to remove the window a/c unit and pull the cool air from outside, possibly with another 6" inline fan on the other end of the tent. Or just pull in cool outside air with one of those window fans I have with 2 fans that are reversible into the bedroom and again control temps with the door inside the bedroom with the door? It just seems like a huge waste to be pulling the RH out and away from the plants when apparently it is needed also? right now I"m not running the a/c. It's 72 degrees outside. 71 degrees in my house, bedroom door open so I'm pulling in air from the whole house? the tent flap is open bout 1/4 of the way, exhaust fan running, inside tent fans running, and humidifier chugging along inside the tent. it's 80 degrees with 39% RH inside the tent. I can turn off the fan and it's like 78 degrees and 48% RH. What am I missing here? I'm so sorry for the rambling on, I've done searches, watched you tube vids and everyone says you HAVE to run an exhaust fan. I'm really confused, seems easier and cheaper my way w/o the dang exhaust fan. I have a Viparsrectra VP2000 and two mars hydro 600 led lights in the tent. I keep my tent clean too. Again so sorry for length, trying to give all pertinent info and such. I really enjoy the emails I get from Nebula, very informative.

[bboyfromwayback]

With your setup, especially being secluded with scent not being a concern you definitely don’t need a filter. If it were me I’d get rid of the intake fan and just use the exhaust fan if needed. Since your growing autos light leaks aren’t a issue so you could just leave your tent unzipped if you wanted. The need for a exhaust fan is for people like me who have to keep scent under control so i keep my tent zipped up tight and the exhaust fan pulls air in from the vents at the bottom of the tent so there’s always fresh air circulating instead of stagnant air. Seems like you could leave your tent unzipped with a fan blowing on your plants for air and you’d be fine

[garybob69]

Thank you very much. You've put me at ease. I have a project going now to go away from the window A/C. Bought one of those portable ones that vent out the window via 6" hose. With a thermostat on it maybe I can control temps in the room a bit better. I'll make a plug for the window to accept exhaust for A/C and a 6"starter collar with damper to pull in outside air when it's cooler outside with an inline fan. Obviously it's a process, but I was just thinking about unhooking the filter. Would be more efficient at venting tent if need be. I really don't get odors, maybe I'm not much of a grower, only doing 2-4 autos at a time, after and sometimes during outdoor season depending how many are outside. We're allowed 6 plants legally here where I'm at. Thank you for your input.

[bboyfromwayback]

No problem! I have a portable ac in my grow room and they work very well. You want to keep your temp from 70-85 with humidity 50-60% during veg and mid 70’s at 50% humidity during flower for best results. A good exhaust is a must when everything is zipped up tight inside a tent but you have an ideal setup! It’s exactly how I grew before we had kids. Out in the open in a spare bedroom. I only put them in the tent at night to prevent light leaks but that’s not a concern with autos.

[Shankemdirty]

Now these are not recommended temps and rh but i have grown just fine in 80F temps and 30% Rh i keep my tentflaps closed with one side window open that won't get light in it.

My Ideal temps i like to keep are

70F to 75F / 50%Rh to 70%Rh

Max and min temps i accept and don't stress over are

70F to 80F / 40%RH To 70%RH

Now i mastered my temps in my grow space letting the rh in the room go near 80% put mold on my ceiling outside the tent so try to keep it 70Rh and under and i try to keep the temperatures under 80F if it goes over 80F i correct it but 80F is fine in my opinion letting it get cold under 70F is kinda bad as well 65F here and there wont hit to hard but try to correct it.

ive struggled most with getting Rh down but i open the room if it is too cold outside to open the window getting Rh up is easy just gotta buy like a $50 Humidifier i also mastered heat with this heater https://www.amazon.ca/gp/product/B07DGFV191/ now it is $85 but here is why i like it.

Now it has 2 Settings 1000 watt mode and 1500 watt mode and a fan mode I have only had to use the 1000W mode and it has a auto on and off Feature with a Adjustable Thermostat so the power consumption is not that much cause it heats the room to the desired temps and turns off then when the room temperature goes below 70F for my settings it turns on heats the room back up to 75F and shuts off again

All items i listed are in Canadian currency

Last thing is i use my inline fan just to take the hot air out of the tent and it blows it in the grow room with my setup like this my bedroom temperatures are slightly different from inside the tent and by being able to adjust the bedroom first it makes my tent have less a dramatic change to the temperature which keeps the tent be able to stay closer to the temperatures i need while the room temps are the ones doing the most change Smell is not a problem for me so thats why my way works for me

Took me basically 2 years to master temperatures in my grow tent and the bedroom with the grow tent.

[Shankemdirty]

I love this heater i got it 2 months ago and i can go to sleep knowing that my plants are not gonna freeze during the night say if the temperatures outside the house change cause i am in canada and i know it will shut off if it gets too hot and it has Fire safety features with tip over features Ect. First time i seen it turn off and back on blew my mind lol

[garybob69]

Yes, I think maybe I need to keep bedroom door closed most of the time where the tent is. That in itself might help to regulate the temps. I have a humidifier in the tent. Mostly it's pretty dry here where I'm at, I'm always trying to raise it, of course the a/c is going most of the time also. I don't have an issue with cold. I can keep a steady 40-50 % RH pretty easily and maintain temps between 70-80 degrees. Perhaps I'm just overthinking too much? You think? Thanx for your time, I do appreciate it.