OK, I see what you mean now. Yes, that was scotch tape - I had a probe there to check the temp but it was removed earlier today when I took everything out of the tank for cleaning since I didn't need it anymore.
I hadn't heard that scotch tape could cause a problem (it's never gotten stuck on her before) but I'll make sure to avoid it in the future - thanks for the tip.
Although scotch tape isn't as adhesive as some others, tape of any kind inside an enclosure is definitely something to avoid moving forward.