U K - Can you recommend a "tried and tested" stone cleaner?

Question

My front garden patio stones are looking tired and I can't afford to replace them. A good clean would make a world of difference.

Answer 1

you can get a gallon of brick acid for about 5 pounds from wickes, brush it on then hose it off, done

Answer 2

Any jet washer will do a good job. Just remember to seal them after.