You can use any salt that is designed for home water softeners or any table salt for that matter. I would not use salt used for ice melting as most of these contain other chemicals.
If you use water softener salt pellets you may have to crush them for a DW system.
I am always amazed how much money people waste on all kinds of stuff in life, we should all question everything we buy and ask is it really necessary ?.
Plastic trash bags, paper towels, paper napkins, bottled water, Vacuum cleaner bags and almost all brand name items at the grocery store, I never buy any of these items, let a alone water filters for refs, special cleaners for washers and dishwashers.
