Use Lemon or Lime juice, simply fill bath to level of stain, and add copious amounts of either juice, then scrub gently with non abrasive scourer.
The acid in the juice is natures natural descaler and cleaner, also works great on shower head, just put some lemon juice in a jug place shower head n for about half an hour, then rinse. All limescale will be removed.
Hope this helps
Jase, October 2008
