Then don't boil them for extended periods of time.
When cooking food to make it safe enough to eat, the generally accepted temperature is 165 degrees Fahrenheit (74 Celsius). This is well below the boiling point but should be hot enough to kill anything living on the rock that may harm your scorpion.
Just bring the water up to that temperature and hold it for several minutes.
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If your emperor scorpion stops eating, don't panic.
Be nice -- you were a noob once, too
"Never ask an engineer to explain something, because he will."