I use a water softener to remove calcium. It also removes magnesium and
iron to a lesser extent.
I recirculate my water thru it when necessary to maintain 150CH
My fill water is over 500CH and over 300 TA.
What I know for sure is that it works. It raises my salt level and I think my
TA goes down a bit and PH up a bit. I was not to specific about before and
after measurements.
I have not seen much for discussion on the use of water softeners on this
forum.
I hope the CHEM GEEK will follow on and give us the break down of what
the water softener removes and adds to the pool and its possible effects.