This stuff really works ! Ten out of ten.
We had been trying to remove dark limescale stains in the toilet for weeks, but we couldn't shift them with various cleaners from our local supermarket. Then we found out about Spirits of Salt.
I turned off the water, then flushed the toilet to reduce the volume of water in the bowl. I then added one bottle of the Spirits of Salts to the toilet bowl and vacated the room - leaving the window open - as there was a chemical reaction going on in the bowl. After an hour, the reaction had stopped, and the limescale had completely gone. One flush later and all was well.
Be careful with this stuff, it really works ! Follow the instructions, and don't breathe the fumes.
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