Black staining on tiled shower recess floor waste chrome grille.

Hi Dr. Chemical,
My house is just over 5 years old and I replaced my tiled shower recess chrome floor waste grille about 2 years ago and it needs to be replaced again. I have tried soaking it overnight in bleach (I have since read your article on the effectiveness on bleach), Easy Off BAM Bathroom Cleaner and Ajax Professional Bathroom Cleaner but nothing has any effect on it. Any ideas?

30540cookie-checkBlack staining on tiled shower recess floor waste chrome grille.

Leave a Reply

Notify of
Brian Fox
Brian Fox

Hi all. I have the same problem and have found that CLR diluted with clean water removes the black stuff very effectively however it still come back so is a never ending clean job:(
I put the solution in a bucket and place the grates in for a while. I then just scrub with a fingernail brush and the stuff just cones off easily.
I have also treated the area directly below the grate in the floor in the hope of cleaning it all up but no joy.
Don’t want to replace the floor wastes as this will open a can of worms in regard to the membrane. Very frustrating.

Dr Chemical

Try oven cleaner. If that doesn’t work, Brasso and a bit of elbow grease should work


Try oven cleaner, then jiff, then brasso, then sand paper