I have black residue developing along the seams in my bathroom (standing shower). The residue seems to be growing on the white caulking done along the seams. I tried to remove it using the "Scrubbing Bubbles Bathroom Cleaner" but it did not work.
Is there another way to remove it without damaging the caulking?
I do have similar black spots appearing near my kitchen sink and bathroom sinks, but not as big as in the shower area.