Any help or suggestion will be appreciated. I have a 3x3x72 tent, I know theirs a lot of different ways to ventilate, the tent is in my basement and the temps are 60 to 65 year round. I’m running a passive style ventilation right now, I pull air from the top down through the bottom of the tent, I have my fan and carbon filter outside the tent. It’s hooked up to an inkbird temp controller that I have set to come on when the temp gets to 77. It cycles off and on every 8 minutes usually. The temp drops to around 73 before heating back up. I have one fan at the top intake blow blowing down and one about midways of the tent. The humidity is low in my basement usually 40 percent so I have humidifier with a humistat build in so the humidity stays between 60 to 70. My main concern is when the lights are off, I’m doing autoflowers so I’m running 20 on 4 off. The temp s drop to around 65 to 67 in those 4 hours so my exhaust fan doesn’t come on. The humidity stays about 65 to 75 percent during the off cycle. Is this ok setup or should I try something different?
Mine do the same. It is, what it is. At $200/mo without heating the lung room, no heater makes sense, for me. I have wintered in 45 degrees for 4 hours, and we lived. My tent cools better with intake or static intake on bottom and top exhausting (filter internal or external with fan in tent for noise reduction). Filter or exhaust top vent exiting. Suck or MOVE the hot air out, not mix and push, IMO. I can control my fans for cycle or continous (slower) operation with smaller temperature swings,if desired. Welcome and good growing to you. I wouldnt worry about 40%RH, lights off will be at 70%. Cloudline Controllers monitor Temp, RH, and VPD, while controlling fans or equipment for multiple operations.
Recent forum posting @Ickey posted in :Ac infinity duct fan (thread posting on forum)
displayed other information about ventilation. Good read.
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Indoor Garden Air Circulation Setup
Thanks for the repsonse, I just have a basic ventilation system. I’ve been a guerrrila Gardner outside for 30 years so the indoor setup is a little tricky. I’m already wanting to upgrade to ac infinity ventilation for the controllers. Thanks again
Those conditions are great for veg’n, seedlings will need it a little warmer…around 76-85 but for 4 hours only I don’t think that’ll stall growth. Perfect flowering temps, RH will need to be around 45-55% 
You should also consider that when your exhaust is off there’s no air exchange, and when there’s no air exchange co2 the plants are consuming isn’t replenished. I also grow in basement with similar conditions, but make sure my exhaust runs 24/7, just at lower speed.
@dbrn32 i have a 4x4 tent. I only have a 4” exhaust fan connected to a 4 in carbon filter. Everywhere I have read says at least a 6” for a 4x4. When my fans on it is creating a negative pressure( side of tent sucked in). No I have my fan currently set to be on during lights on. And off when they go off. Would you say I should put a speed controller on my fan and turn it all they at down at night and keep it running?
I know what ya mean about the air exchange, but having the exhaust fan plugged in the inkbird it won’t kick on. I tried using a small personal space heater last grow of 2 small plants but that dry heat blowing across the plants caused the leaves and some small flowers to get crispy late in flower even with my humidifier on at 50 percent. I originally had my ventilation taking in from the bottom of the tent and exhausting out the top but couldn’t maintain a warm enough temp. That’s why I changed it to pull in air from the top of the tent down to the bottom. I need to invest in an ac infinity ventilation system but my wife is already about to divorce me!!! Lmao
Absolutely, oscillating, circulating, and exhausting fans need run 24x7, just as @dbrn32 said, slower during lights off. Lights off RH increases from 45 to 65-70, easily in my tents. Seedling tent has seedling heat mat (tent has 300Watt (150 actual) LED, fan, and heat mat, 20/4 seedling hours. temps 55-75, seedlings doing good. Clones sharing tent and seedling mat, status unknown.
Cloudline 67 or 69 controllers recommended. Warning, 69WiFi compatible only on house 2.4Ghz wifi
AC-I Cloudline controllers will handle compatible equipments. Potentiometer (dial) controlled fans can only operate at set dial speed, Off or ON condition, as outlet controlled operation.
The expense of AC-I controlled system is difficult on short term financing. Long term operations with enhanced time stability (Cloudline Controllers have battery back-up) will provide insurance againt tPNW storm induced power-outages timing fluctuations. Monitoring tent conditions with positive control protection in my absence, allows me to sleep or travel for daily tasks.
I get it @DEEPDIVERDAVE you like ac infinity. As I’ve stated before I don’t want ac infinity. It’s too pricey. And as stated it would be litherally the ONLY piece of aci equipment I have so I would then have to buy special adapters to make anything work. I don’t have to bad of fluctuations in a small room in a small home. Plus I’m hopefully not staying in the pnw much longer so I don’t want to spend a bunch on even more indoor equipment when I may not need it again in a year
Depends on the fan and available controllers. Some of them don’t behave well with controller. And every environment is little different too. If you’re having success i wouldn’t fix things that aren’t broken.
That’s the only reason I was considering changing something. That had me worried
Hard to say this is an issue for you without measure, but choking off co2 during lights on is just as important if not more so than maintaining temp and rh.