DanSand staining on Indian sandstone

There seems to lots of people who think that a patio is going to look perfect with no blemishes in the stone ,it’s a natural product which has all sorts of things that settled in it over millions of years when it was formed,it’s a patio outside so all sorts of things will fall on it and all sorts of algae will want to grow on it ,patios can be sealed with various products which will be recommended by the retailer,I think people should stop expecting an outdoor area to remain perfect forever ,everything outside will weather,the sun WILL bleach things and the rain WILL stain things and nature WILL allow things to grow on a patio

Try bleach x not very eco but can get water soliable x add water not neat and brush in x leave for half hour and try power washing again x

I need to have a look,before I suggest a remedy

If your sandstone isn’t grey you could try hydrochloric or hydrophilic acid solutions to remove the grout staining, you could also hire jet wash machine that uses boiling water, if your sandstone is grey acid will turn it orange