i keep having these white stains on my bathroom floor tiles when it dries. i have tried all means to scrub it off but it's still there when the floor dries.

what's the root of the cause? Is there any way I can get rid of it and pevent it from coming back?

the pictures can be found here

http://www.flickr.com/photos/kwanwei/sets/72157623222912019/

i keep having these white stains on my bathroom floor tiles when it dries. i have tried all means to scrub it off but it's still there when the floor dries.

what's the root of the cause? Is there any way I can get rid of it and pevent it from coming back?

the pictures can be found here

http://www.flickr.com/photos/kwanwei/sets/72157623222912019/

During renovations, the tiler usually mixes a bonding powder which is white in colour with cement to strengthen the adhesion between the tile and the cement mix. Try buying acid meant for washing floor tiles and see if it helps in removing the stain. I know it works in my own toilet.