I have worked with DRYLOK® Natural Look Sealer in the past, on my brick walls. Last weekend, I decided to apply it on a cement board that makes up my exterior deck. This sealer comes in a white milky form, but dries out clear and maintains the natural look of the masonry work.
All went almost perfect, until I decided to mix in an old bucket (4 months old) of the sealer to finish the job. I ended up with a thick white film that will not dry out clear, it looks as if I applied white paint to parts of the deck. I know, I should not have used the stored sealer, how do I get rid of this white film? I trying scrapping/sanding it off but that will damage the cement board.