[controversial97]

What would you make the electrodes out of?

Copper will react with the chlorine in tapwater and make an insoluble green scum of copper chloride.

Electrolysis with stainless steel makes highly toxic hexavalent chromium.

Platinum is astoundingly expensive, even for plating.

How expensive a filter is needed to remove 99.999% of the chlorine?

The thing with electrodes is that a fiftieth of a millimeter of non-condutive crap on the surface hugely reduces the effectiveness. Around here the bottom third of my kettle has a tenth of a mil of limescale.

[theincredulousk]

even type II water, which is a standard output of off-the-shelf lab water filtration systems, only has <= 5 ug/L of chlorides, sodium, silica.

And Platinum is like $30 a gram. There is 1/5th of a gram of Gold in a standard desktop computer and Gold is twice as expensive as Platinum.