Where should I put the thermostate probe and why?

[Rickys_Reptiles]

I have often wondered how "water proof" they are. Either way I wouldn't gamble on it. Just my thought.

Well, the probe and cord are covered with epoxy, so even if the probe itself wasn't 100% waterproof - it sure is now! I've been doing it this way for years and have always had a very consistent temperature. To each their own, but this method works well in MY OPINION.