We ground & sealed (two coats porous plus) a white stone floor - originally thought to be limestone, but more likely to be quartzite.
It has since acquired some spots, which won't come out with 1:1 Extreme clean after a 20 minute dwell. We have some Poultice Pro powder - what's likely to be the best product and dilution rate to make up a poultice? Also, any other tips - should floor be pre-wetted or dry? Is 24 hrs the right dwell? Should I tape plastic down, make pin holes?