There are a lot of white spots on the gray tiles of the hotel bathroom floor. How to clean them?

Use sulfuric acid or hydrochloric acid solution. Drop it on the brick surface, let it stand for a few minutes and then wipe it. Pay attention to protect your hands. Amway has a special ceramic tile cleaner, and the effect is quite good.

It can be wiped with turpentine and acetone, and toothpaste used at home also has a good decontamination effect. Tea stains, fruit stains, coffee, soy sauce vinegar, shoe prints and other stains are soaked in sodium hypochlorite diluent (bleach) for 20-30 minutes and then wiped with a cloth. Some stains that have penetrated into the brick for a long time will take several hours to soak.