I have a new 100 watt heater on the way for my 10 gallon and I want to give my 5&A half gallon the old 50 watt heater but that tank has common pond snails. Do you think a bleach solution or salt rinse will kill eggs and adults so I don't get hitchhikers? The snails absolutely love that heater and I see egg sacs on it all the time.
Both heaters are the preset tetra submersible ones btw
You can try rinsing it under tap water and doing a thorough scrub of that heater. I personally wouldn't trust myself with bleach and putting it back in a tank.. Or you can dry out the heater; when I need to dry things out from any of my tanks I leave it in the garage because it gets really hot in there lol.