Hova Bator vent question

[Pipe Dreaming]

First time using this incubator, just wondering about how air tight it seems to be. It has one single hole in the top window with the plug. Should I leave the plug in for the 1st 10 days or leave it open the whole time?
The other incubator I'm using (LG 9200) has 2 vent holes plus several tiny holes all over the top. The Hova Bator seems way more air tight with the lid sitting snug inside the the bottom half.
I've heard decreasing oxygen levels for the 1st 10 days can be beneficial, making stronger embyros, but this seems extreme.

 

[lazy gardener]

I'm a big fan of breathing. Never saw a hen covering her nest with plastic.

 

[Ridgerunner]

I’ve heard the same thing from someone I consider a reliable source. Later in the incubation it is very important for the chicks to be ab le to breathe fresh air through the porous shell but supposedly they are benefited by not having much, if any, air exchange the several few days.

I have the Genesis Hovabator 1588, older model, with just one vent on top. I leave it open the entire incubation period. I figure if they are hatching 1,000,000 chicks a week all through the year they may notice a benefit but as few chicks as I hatch and as few times a year as I hatch, I probably won’t recognize any great benefit. Hard as it is sometimes I try to not overthink it.

 

[Pipe Dreaming]

Thanks for the insight. I'm going to go with my gut and pull the plug. Having something that sealed up just doesn't seem right to me.