Thanks for all the info. We've been using our tap water for strictly rinse steps all else is distilled mixes. So I could see how chlorides if present could get to the other solutions over time. We've only ever had one customer complain of such pitting, but then not everyone is of the same particular mindset... and I guess we've just never noticed it on any other parts. What bothers me about this possible solution (chlorides) is that the parts are not evenly pitted, just certain areas or spots on the part and not every part in the batch gets pitted, just a select few... which would logically point me to something outside the solutions. I would have to guess my logic is flawed from inexperience
I guess I'll see if I can find a test kit for chlorides.