Electro-chlorination can be ...

Electro-chlorination can be either with a membrane system (producing chlorine gas or a high concentration of hypochlorous acid), or non-membrane (producing a lower concentration of hypochlorous acid, typically < 1%).  The non-membrane systems  have the advantage of low maintenance and lower operational attention, with the feed water quality being less stringent.  Either system requires cleaning of the electrodes (acid wash) from time to time, while the membrane systems also require membrane flushing and replacement.  Pre-softening the water helps to minimise scale formation on the electrodes.