I don't know how I can forget that tape inside the enclosure is a no-no. I totally forgot about that. When I checked just now, the tape was already stuck to one of the snakes and the other snake working on getting tangled up with it as well. i removed the tape very gently using water and removed all the rest.

I'm using a brand new herpstat2. Prior to being installed on this PVC cage, the probes were living between the bottom of the plastic tubs and the heat pads where the snakes were living. They have not been wet or dirtied at all. But having said that, I just checked and the humidity in both cages is now reading at 100%. It's late so the light was off but when I went to remove the tape, I noticed a lot of moisture condensed on the glass. I put a second hygromter in one of the cages and it's reading is up to 80% and still rising. So it seems this reading is correct too. Perhaps the 0% reading earlier was a result of not giving it enough time.