Page 1 of 1

Posted: Fri Aug 03, 2018 8:35 pm
by Millsabelle
Hi. I know this will have been covered but can't find the answer. I have laid a black limestone patio and got mortar staining all over. I have asked landscape gardeners and done Google searches and all except this site say to use acid based cleaners. Reading through paving expert it says under no circumstances use acid but does not seem to advise what to use, I can only find sealers and colour enhancers. Really hoping I haven't wasted a load of money.
Cheers.

Posted: Tue Aug 07, 2018 11:11 am
by Tony McC
God knows why other sites are suggesting the use of hydrochloric acid! That stuff should bnever be used on limestone, and never, ever, ever used on black limestone. Eejits!

You *could* try phosphoric acid - that does work on some occasions - not always, mind, but sometimes. Otherwise, it's as I say on the main website: try a colour restorer or grit blasting, or opt to have the affected flags replaced.