"~ jan JJsPond.us" wrote in message
...
How is the resin regenerated? Is it regenerated with salt?

Yes

If it is regenerated by salt the output of the bed is going to be high in
sodium (salt).

Sodium ions yes, Salt (Sodium Chloride) no.

A water softener does not get rid of chlorine, unless there
is carbon in the system and it would need to be replaced on a schedule.

.....is as I understand it too.

I think that using Softened water for any kind of fish is not a great idea.
Its very much too soft & depleted & then again much too full of Sodium ions
to be good for them (which is why we humans shouldn't drink it either!).