Ferrous sulphate stains and indian sandstone - As above

[karl 1974]

hi i was trawling this fabulous website for info on weed and feed stains ( ferrous sulphate in particular on indian sandtone), and gather that they are particularly stubborn! has anyone else had experience of this, does it eventually go away?? how long must i wait, tried cleaning it with dilute caustic soda with no luck, just an overall clean to patio. ???

[RAPressureWashing]

Is the Patio next to a lawn and a lawn feed has been used?
And it now looks like a rust stain?
If yes then these type of stains can be a bugger to shift, DON'T use a bleach wash on this as it can set the stain making it look worse then it already is, you might have done this using the caustic
Can you post a photo of the staining, there are chemicals that can reduce the stain, but are not nice to use.

[karl 1974]

hi ganger thanks for replying, yes it is definetly ferrous sulphate stain form a weed and feed on the lawn next to patio applied few days earlier
, not sure how to post images unfortunatly
the patio has lots of pimple,pot marks on it, rust coloured. weren't there before:(
hope i havent cured them to the patio now with the caustic??
would power hosing them clean them off? or leave them more exposed? they may eventually wear off or be hidden i suppose as patio ages?
karl :rock:

[Mikey_C]

info on posting photos is here

[RAPressureWashing]

Hello Karl,
Thanks for the pm, no power washing alone won't remove the stains.
Send me the close-up of the stains when you can and we can take it from there.

[karl 1974]

thanks ganger!

[karl 1974]

and thanks for the info on posting images mikey!!:)