Hova-Bator Ventilation Hole Question

[barnkat]

I've got a Hova-Bator, the picture window one with three vent holes in the top, two of which have red stoppers in them. Is the middle hole above the fan enough for ventilation, or am I supposed to open the other two? I've got the 2 stoppered up, worried there's not enough air getting in/out.

 

[speckledhen]

I keep my vents plugged till they begin hatching. There are holes all the way around about an inch above the bottom of the bator, in case you didn't know. That's where the air is drawn in, so there is enough air with the stoppers in place till hatch time.

 

[barnkat]

Totally didn't notice those little holes at the bottom. Duh!