fan vs heat?

[austin87]

So as I mentioned yesterday I had a couple seeds sprout. Following some advice I received here, I set up a fan to give them a gently breeze. However, the garage pretty cool and the moving air sucked temps right out of my soil and dropped them down to high 60s/low 70s, even with the heat mat and light. In the photo below the fan (not pictured) is off to the left 4-5 feet.
 
I'm concerned with damping off for the sprouted guys but concerned with soil temps for the ones that haven't germinated yet. I think at this point it's probably most important to keep temps up, even at the expense of the fan??? 
 
Thanks everyone!
 

 

[alkhall]

I have never used a fan, never had any issues with damping off.
 
I would guess it depends on the medium you are using and how much you water, and whether there is natural air circulation.
 
Yes, it is quite important to keep the soil temps ~80°F - 85°F for most supers.
 
How are you checking soil temps?

 

[austin87]

I have never used a fan, never had any issues with damping off.
 
I would guess it depends on the medium you are using and how much you water, and whether there is natural air circulation.
 
Yes, it is quite important to keep the soil temps ~80°F - 85°F for most supers.
 
How are you checking soil temps?

I have a heat mat with a thermostat (thermostat is set in a central cup), then I spot check other cups with my Thermapen. Using organic potting soil with additional perlite that I added myself for medium.

 

[rjacobs]

This is one reason why most people germinate in tupperware or straight zip lock bags with paper towels.  You need different environments during different cycles of the plants life cycle.  You are trying to combine these two environments and you are having difficulty finding a balance.
 
I wouldnt worry about the fan at the stage your seedlings are at personally.  Just take the zip lock off of the solo cup.
 
Most people want a fan on their plants as they start to get larger to help strengthen the stems so when they go outside they dont fall over.  A secondary benefit is helping dry a little of the top of the soil to prevent fungus.

 

[juanitos]

yeah fan helps more once they get a few leaves.
although the fan does help dry out soil to prevent damping off and gnats since some people overwater.