For the thermostat, the probe goes on the outside of the enclosure between the tank and uth. So it won't malfunction due to water or in tank factors.
Thermometer probes and wires are not a problem in tank either. You can hot glue the wires down(but not the probe itself) if you're worried.
There is as much risk to feeding frozen/thawed as live. Just different risks. Both have to be done responsibly. When feeding live, the best you can do is feed smaller and more frequent than large and less often. Crawler/small rats are harmless. It's the adults that are potentially dangerous. Also be vigilant and watchfull during feedings in case something view wrong.
I can list a few things about frozen and live that can go good or bad, but I'm not trying to convince you to change feeding methods. If feeding frozen works for you, great! But I just wanted to point out, that there is a risk with frozen too.
A small pond is safe and ok to do. I know some members have one in their tanks for their snakes.
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