Influence test with reduced water surface tension by physical, magnetic treatment in the circulation of an oil+water solution.
Performed with the DIN-Norm test stand at the TÜV institute, Essen, Germany.

Samples: Water hardness 393 ppm (3,9 mmol/l) ------- Samples: Water hardness 125 ppm (1,3 mmol/l)
Solution in test: 95% Water + 5% Hydraulic oil

On both photos above are the Left samples: Without conditioning - Right samples: With conditioning
The right samples with significant more separated oil, indicates a reduced water surface tension.
High water harness (left photo) contribute to more oil separation that with lower water hardness (right photo).