I use these. https://www.amazon.com/gp/product/B08Y6CYVT9/ref=ppx_od_dt_b_asin_title_s01?ie=UTF8&psc=1I didn’t know there were humidity gauges with probes. Which brand do you use? I have thought that the humidity has got to be higher within the plants with all I’m doing. I don’t have a fan blowing in the enclosure but I have one blowing in the room it’s in.
They're inexpensive, have large numbers for both temp & humidity, they're in Fahrenheit, and I can compare them against each other for accuracy (which has not been a problem).
There are other "brands" but I suspect many/most come from the same factories in China.