What salt mix do you use ?

I've looked around and havent found a recent thread on salt mix. I also have seen in the past company's change there level in there mix or just not be consistent. I'm curios what salt mix you use, why and what the levels are when mixed? Maybe you use NSW like some on here I'd like to know from where , levels and how long you've been using NSW?
NSW is an option for me I've just been sceptical because of bacteria and pollution but I read a thread that paulb uses water from Manhattan? Curios how that's working out?