You are not going to get an accurate CO2 sensor for $27. You're being misled into buying cheap Chinese crap.
An accurate CO2 sensor is much more expensive. I would not trust the readings of the sensor in this blog. It's going to be off by over 100ppm, especially if there's a lack of good airflow.
Senseair is a Swedish company and definitely not "cheap Chinese crap". Do you know about any research that confirms your statements about the accuracy?
I believe that some of the more expensive sensors are more accurate, but this cheap one may be a good enough solution in some cases (e.g. indoor air monitoring for DIY projects).
The research has been done by the weed growing community. I don't know any professional growers using sensors outside of the American Scientific as the cheap ones are inaccurate and failure prone.
It seems thoughtfully designed.
I especially like the warnings in the beginning.
Usually I prefer a higher density of information, but this is not too shabby.
An accurate CO2 sensor is much more expensive. I would not trust the readings of the sensor in this blog. It's going to be off by over 100ppm, especially if there's a lack of good airflow.
https://www.atlas-scientific.com/product_pages/probes/ezo-co...