*7.1.12 Treatments with electromagnetic fields*

Electromagnetic fields have the ability to increase the interaction of the Ca2+ and CO3<sup>2</sup> *−* ions present in seawater, increasing their nucleation and precipitation in CaCO3. Below 35°C, CaCO3 precipitates in the form of aragonite instead of calcite, resulting in being less adherent and less insulating [3, 85, 86]. The precipitation process of CaCO3 reduces the superficial tension of the water, minimizing the adherence of microorganisms, and affects the intermolecular union of the extracellular polymers, weakening the matrix of the biofouling layer and diminishing its capacity of adhesion to the surface [7]. In addition, CaCO3 entrainment by the seawater flow produces an erosive effect on the weakened biofouling layer that reduces its thickness [87, 88].
