SW201 installation problem

I have WS201 pump and Siemens electrical motor and I installed together but I faced two problems:
1- I have to manually shutoff every time at standby
2- The salt water always damage pistons and o-rings
So what more setup should I make to override these two problems?

Quit using salt water. Maybe invest in bottled water?

Thank you,
What about manually shutt off problem?