Wikipedia说 这种东西就是骗人
Non-chemical devices
Some manufacturers claim that the electrical devices they produce can affect
the interaction of minerals with water so that the minerals do not bind to
surfaces. Since these systems do not work by exchanging ions, like
traditional water softeners do, one benefit claimed for the user is the
elimination of the need to add salt to the system. While particle size
reduction and plant growth promotion have been claimed, such systems do not
remove minerals from the water itself. Rather, they can only alter the
downstream effects that the mineral-bearing water would otherwise have.
Examples are remediation of calcium scaling[11][12] and remediation of salt
crusts in soil.[13] These systems do not fall within the term "water
softening" but rather "water conditioning".
Similar claims for magnetic water treatment are not considered to be valid.
For instance, no reduction of scale formation was found when such a magnet
device was scientifically tested.[14]
The above methods, of distillation and reverse osmosis, are the most widely
used two non-chemical methods of water softening.