Positive and negative effects of calcium On the one hand, hard water delivers valuable min- erals such as magnesium and calcium that are essen- tial for human beings. On the other hand, calcium carbonate deposits in water pipes for tap or cooling water lead to problems including blocked pipes, greater biofilm formation and corrosion. Removing these layers of deposits is a mechanically intensive process and requires limescale removal products. The water can be preventively treated using chemi- cals or ion exchangers, but these are harmful to the environment and must also be properly disposed of. Moreover, they completely strip drinking water of essential calcium ions, which must then be re-added. Electric antifouling (EAF) systems offer a sustain- able alternative. These devices emit electric pulses into water pipes in order to reduce limescale depos- its without removing water-borne minerals. Al- though EAF systems are already widespread and have been the subject of numerous studies, their mecha- nism of action is yet to be fully explored. New calcium carbonate microstructure discovered The interdisciplinary team led by Dr. Sina Saxer (FHNW School of Life Sciences) has demonstrated a reduction in limescale deposits in a feasibility study with EAF devices from project partner Hydro Service Schweiz AG. The researchers have also identified a previously unknown, almond-shaped microstruc- ture of calcium carbonate, which they call μAl- monds. In the Nano-Argovia project of the same name, μAlmond, the team will now use X-ray absorption microspectroscopy to analyze this new microstruc- ture in detail and to investigate, in real time, how it forms under the influence of electric fields when EAF systems are used. The researchers are also ex- amining how various forms of calcium carbonate (calcite, aragonite, μAlmonds) can be absorbed by human intestinal cells. Should μAlmonds exhibit higher bioavailability, they could also be of interest as dietary supplements or biomaterials. With a planned duration of two years, the proj- ect aims to clarify the mechanism of action of EAF systems and, by doing so, to drive the development of tailor-made solutions for homes and industry. At the same time, the findings in relation to μAlmonds could pave the way for innovative approaches in nutrition science and materials research. Understanding antifouling systems and calcium carbon- ate microstructures In the Nano-Argovia project μAlmond, researchers are exploring funda- mental questions regarding the formation of calcium carbonate (CaCO 3 ) crystals in water systems. As part of this work, they are studying the mechanism of action of an electric antifouling system and analyzing the significance of various crystal shapes for water quality and health. Collaboration between: FHNW School of Life Sciences Paul Scherrer Institute Hydro Service Schweiz AG (Wohlen) Further information: Nano-Argovia program FHNW School of Life Sciences Paul Scherrer Institute PSI Hydro Service Schweiz AG 10 SNI INSight June 2026 Nano-Argovia program