Hardwood Floor problem:
I was light sanding with steel wool after my first coat of finish. I wiped up the floor with a damp cloth and areas of the floor now have some black areas. I believe this is an iron stain from the steel wool and damp cloth.

How can I fix this? Do I have to sand down the floor again?

Thanks.

ur gonna have to sand the areas damaged enough to remove the damage.
you probably used a waterbase finish??

your not supposed to use steel wool on waterbase for that very reason..

Steel wool makes a big mess and we contractors haven't been using them for many years now (generally speaking) Once you re sand and touch up your stained areas, go to a rental store or flooring supply store and get 220 grit screens or a 3m maroon abrasive pad and use that . 3M gold stikit abrasive tape can also be used under the buffer to the same effect.