seeds Starting seeds in a grow tent - do I need ventilation/exhaust?

[blueapplepaste]

Normally my seed starting area is my office, but as I'm still WFH, I can't have neon lights in the background of all of my Zoom meetings. So I've invested in a grow tent and an LED quantum board to hopefully keep things cooler (my current fluorescent lights get super warm).
 
Anyways, virtually all info I've found is for growing cannabis. I've tried searching this forum, but haven't found much info either (could be using wrong search terms).
 
But do I need active ventilation like what is used for cannabis? I'm not worried about any pungent smells. And I will be checking on them daily, so there will be air exchange when opening it up.
 
I will have a couple of small fans set up inside just for some air circulation and to stiffen up the plants.
 
Thanks for any input from experienced grow tent users!

 

[peppersproutfarm]

I would say no. Since this is just a seed starting station you're not going to have the plants there for the entirety of their life. It's not going to need nearly as much fresh air as say a cannabis plant would as you referenced. I'm pretty sure as long as you have fans going to strengthen them you will be fine. I start my seeds in a closed closet. With a fan running of course

 

[The_NorthEast_ChileMan]

but haven't found much info either (could be using wrong search terms).

 
Try putting "quotes" on the search term="seed starting" or "tent fan"  then using advanced search :and title only..
 

 
 
 

 
 
Additionally, select the forum most appropriate. Hope this helps!
 
 
Show me your seed starting setups!
Seed starting system using plastic water bottles
Another seed starting method
Preferred Seed Starting Method
 
_

 

[Siv]

Personally, I found that the tent gets a lot hotter than ambient if it's all closed up, even with LED lights. I tried adding some janky ventilation (a small fan in the tent and another in the exhaust port) and it didn't really help much so I just left the door unzipped which helped a lot more. Bear in mind that this was during summer so the house temp was a lot warmer than it is now. Get a cheap thermometer to check the tent temp and if it's super high then consider leaving the door ajar. If your house is relatively cold then the tent upping the temp by 10 degrees may actually be beneficial for your seeds. But if they're too hot, you may get more problems. I also had a white fly infestation in one of my tents.

 

[solid7]

Ventilation is an absolute requirement, when you can start quantifying CFMs of fresh air for a plant.  At the seed stage, put a fan in the tent, and call it a day.  I usually find it best to not point the fan directly at young seedlings.  Create diffused air flow. (vortices)

 

[solid7]

Also, to add to what Siv says - the fan is all about moving air, not anything to do with temperature. (moving heat out of a tent is just a knock-on effect, leveraged for efficiency) Maintain your temp requirements some other way.  If you can't control the temp on a budget, you may want to just have a rethink about the tent, for now.  I start seeds in my closet occasionally, and I get by on just normal room temp.  The closet, obviously, has a door.  

 

[blueapplepaste]

Thanks for all of the replies and additional insight!
 
 

Personally, I found that the tent gets a lot hotter than ambient if it's all closed up, even with LED lights. I tried adding some janky ventilation (a small fan in the tent and another in the exhaust port) and it didn't really help much so I just left the door unzipped which helped a lot more. Bear in mind that this was during summer so the house temp was a lot warmer than it is now. Get a cheap thermometer to check the tent temp and if it's super high then consider leaving the door ajar. If your house is relatively cold then the tent upping the temp by 10 degrees may actually be beneficial for your seeds. But if they're too hot, you may get more problems. I also had a white fly infestation in one of my tents.

 
Thanks for information. I'm not too concerned with temps. I keep my house pretty cool in the winter time, around 66º during the day. So a 10º bump in temps will be perfect.
 
 

Ventilation is an absolute requirement, when you can start quantifying CFMs of fresh air for a plant.  At the seed stage, put a fan in the tent, and call it a day.  I usually find it best to not point the fan directly at young seedlings.  Create diffused air flow. (vortices)

 

Also, to add to what Siv says - the fan is all about moving air, not anything to do with temperature. (moving heat out of a tent is just a knock-on effect, leveraged for efficiency) Maintain your temp requirements some other way.  If you can't control the temp on a budget, you may want to just have a rethink about the tent, for now.  I start seeds in my closet occasionally, and I get by on just normal room temp.  The closet, obviously, has a door.  

 

 
Yeah, the fan I mention was simply to stiffen them up by having some "wind" moving over them. Not for temp control. I'm not worried about temps too much. Even by the time these go outside into the garden, the house is pretty cool. So 10-15º increase inside the temp won't hurt anything at all.
 
I was more curious if the mere act of opening the door to check in on them daily would facilitate enough airflow to ensure they had adequate CO2/O2 exchange and to just keep things fresh. I have no issue getting a vent fan to circulate fresh air if needed, but if it's not then I'd rather not spend the money either.
 

 

[solid7]

I was more curious if the mere act of opening the door to check in on them daily would facilitate enough airflow to ensure they had adequate CO2/O2 exchange and to just keep things fresh. I have no issue getting a vent fan to circulate fresh air if needed, but if it's not then I'd rather not spend the money either.
 

 
As someone else mentioned, I probably would just leave the door unzipped.  But in any case, there is no concern over ambient environment.
.
I probably couldn't tell you when the actual need for a circulating fan arises, because I just default to using it.  What experience has taught me, is that when you do need it, you know in real short order, and it's because your plants have had their progress retarded.  For me, it's more sensible to "buy once, cry once".  You don't need much of a fan for seedlings - but fans are cheap, and you can pretty easily find a one size fits all for a small grow tent.  Otherwise, I have found cheap USB fans for as little as $4.
.
The oxygen and CO2 requirements for seedlings are so small.  No need to waste a moment of time worrying about that.  If anything, later on, you'll need to be more concerned about ethylene, when you start getting lots of plants, or plants + pods.  But for now, plant 'em and go.

 

[blueapplepaste]

 
As someone else mentioned, I probably would just leave the door unzipped.  But in any case, there is no concern over ambient environment.
.
I probably couldn't tell you when the actual need for a circulating fan arises, because I just default to using it.  What experience has taught me, is that when you do need it, you know in real short order, and it's because your plants have had their progress retarded.  For me, it's more sensible to "buy once, cry once".  You don't need much of a fan for seedlings - but fans are cheap, and you can pretty easily find a one size fits all for a small grow tent.  Otherwise, I have found cheap USB fans for as little as $4.
.
The oxygen and CO2 requirements for seedlings are so small.  No need to waste a moment of time worrying about that.  If anything, later on, you'll need to be more concerned about ethylene, when you start getting lots of plants, or plants + pods.  But for now, plant 'em and go.

 
Zero worry about ethylene build up here. These will be in the ground before I ever let them set any pods.
 
But as you said, maybe better to just do it. I'll order up a smaller fan in order to vent in fresh air along with some smaller fans to circulate around the plants. They seem pretty inexpensive.

 

[blueapplepaste]

Thought I'd give an update if anyone was interested in seeing the final set up. All seems to be going pretty well!!
 
It's a Vivosun 4x4 tent, Mars Hydro TSW2000 light, AC Infinity Cloudline 4" exhaust fan, and a Honeywell oscillating fan.
 
I have the exhaust fan set to pull air in through the bottom. All of the vents except the bottom are closed off. The oscillating fan rotates and blows pretty slow on the low speed, which gives a nice, gentle rustle to the seedlings.
 
The light is 36" above the top of the trays, and I have it set at about 80%. I have the power supplies outside the tent, as the lines from the power supplies to the fan were super long. Seems to help a lot with keeping things cool. Temps directly under the light don't get above 25ºC (77ºF), which is perfect. It's a little cooler towards the edges. Currently set for 16/8 on/off.
 
So far about 15 different pepper types have come up. I also started some more leafy greens for a final harvest before it warms up. I'll be putting them out into the garden in a couple of weeks.
 
So far I'm digging the set up. The upfront cost wasn't insignificant, but I think it's making a lot of things easier. Definitely will be using it year round to start some of the winter crops indoors so they can get a good start before things really cool of and slow down.