Salt corrosion occurs whenever a salt-based mixture sits on a surface, typically metal. Vinegar is a good method for removing the salt corrosion because its high acidity rate cuts through the salt and breaks it down.
Fill a bucket with vinegar and place your corroded item inside. For items like showerheads and faucets, you need to first remove the item. Within an hour you should see the salt corrosion breaking down.
Depending on the severity of the corrosion, you may need a mixture of baking soda and vinegar. Sprinkle the baking soda over the corroded parts and pour a small amount of vinegar on top. The mixture will start bubbling immediately.
Use a scrub brush to speed up the process and to get into any grooves on the piece. Apply the vinegar, or baking soda and vinegar mixture, and lightly scrub against the surface of the piece.