Explanation

It sounds like a contradiction in terminus. The Small Wonder
promotes the forming of mineral crystals. However not on surfaces
of heating elements or glasswork but in the bulk of the water.
These crystals flow with the water and will not settle. They are
discharged through the drain.
Cleaning properties of water are improved because of the lower
surface tension. (Water feels silkier).
The alternating current through the coil generates a weak magnetic
AND electric field of which the polarity changes many times per
second. This will agitate the mineral ions and water molecules,
starting crystal growth. The Small Wonder is not a magnet. A
magnet generates a very strong static magnetic field and will not
be effective on slow flowing water and on top of that it will attract
particles. Because of the symmetric alternating nature of the
Small Wonder signal, the average field strength is zero so
particles will not be attracted. The generated electric field causes
the Small Wonder to be effective also on slow flowing waters.