Why does a galvanized tank waterlog?
Galvanized tanks waterlog because well water is somewhat deficient of oxygen. So each cycle of the pump when fresh well water is introduced to the tank, it steals a little bit of air from the tank. Before long (no set time, different in all cases) the tank becomes waterlogged and the pump motor is hammering on and off, trying its best to get hot enough to burn up. Which it will before long.