Does anyone know a safe way to descale a bath?
Twice now I have assumed that metal, i.e older cast iron or more recent steel, baths were vitreous enamelled. In each case attempting to thoroughly descale it has resulted in the descaler removing everything to reveal a dark surface. In the first case I used dilute hydrochloric acid - which would be ok on a vitreous surface! In the second I used Waitrose washing machine descaler, which is probably citric acid.
Take this as a terrible warning! .. and since you ask.. In the first instance I was trying to get a good base before resurfacing a bath with 'Tubby' epoxy coating. In the second, just trying to remove unsightly marks! Tubby is a fairly useful product, but it tends to peel away at the edges. Has anyone had complete, lasting success with it?