Corrosion is a complex electrochemical phenomenon produced by the interaction of the pump components with the environment. Generally it is influenced by the simultaneous presence of mechanical stresses. Corrosion can lead to major failures if not properly controlled. The selection of the construction materials of the pump and other system components is crucial to prevent the onset of corrosive phenomena. Visual inspection of the pump and its main components is the simplest way to reveal the presence of anomalies. It should be carried out periodically because the chemical-physical conditions of the environment can change over time.