When I was a lad, I had to shock my well in order to pass a home sale inspection. Well guy said pour one gallon of bleach down the well.
In my wisdom, I figured if one gallon was good, four must be better.
A half hour after pouring said bleach, I noticed "smoke" coming up out of the casing.
My bleach had eaten through the wires to the pump.
I ended up having to replace the pump.