I run an Aranet4, it's set to alert if the co2 goes over 900ppm which is where I notice a dip in cognition or at least wakefulness. I use its API to connect to

I run an Aranet4, it's set to alert if the co2 goes over 900ppm which is where I notice a dip in cognition or at least wakefulness. I use its API to connect to it once a day and download the last 24hrs of logs (it stores 14 days worth on the device). It's expensive - but it's really the best there is IMO. I try to open a window on either side of the house when the co2 gets over about 750~