Hard water

what should i use to remove hard water deposits? I did a search and am confused. I am looking for something that is safe to use. I have heard of white vinegar.
Also how is it applied?

i once used acid from out of an old car battery,it worked a treat , i dipped a rag in it then wiped it on the scale,let it soak a while

Check out Bio Clean. You can apply it with a white scrubby pad. It doesn’t take as much elbow grease as you may think.

For more serious deposits, you may look into Safe Restore, although you should do your homework on it.

http://shop.windowcleaner.com/category.sc?categoryId=89

What personal protective equipment (PPE) should be used with your recommendation? Do you carry an MSDS with your old battery?