All depends on what type of probe it is, and how it's wired. Most of the bulb type probes would have problems directly in the water without some kind of protection, but the thin brown plastic ones are sealed and wouldn't have a problem in water. I think putting a temp probe in the water in a setup like mine would be very simple as I have that one line that captures the air, with just a bolt in the top to act as a cap, would be easy to slip a probe down past that and into the water. Just gotta get myself a probe for that now..
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The UnaClocker
Overclock till it goes BOOM!
Watercooler extraordinaire!