On 18/04/2019 10:58, Brian Reay wrote:

Â*We live in an area with especially hard water and had an issue with a
toilet overflow- fixed some time back. However, it left some stains on
the wall. I had hoped they would fade but they hadn't. Scrubbing and
power washing hasn't helped.

Does anyone have any suggestions, please?

brick/Patio acid = HCl


--
"When one man dies it's a tragedy. When thousands die it's statistics."

Josef Stalin