I assume it's for disinfecting ~ when I were a wee lad many moons ago living in the country our water mostly came from the nearby lake, we cycled it through a big tank/pump thing that chlorinated it & we had to add a few gallons of bleach now and then .

We've had stainless steel sinks in SWMBO's house and no corrosion / staining of any sort from the bleach so far .

The double sink in my house is the original 1923 white porcilain one, the porcilain is fairly porous now so not bright white any more, bleach, white vinegar, comet , ajax, bon ami etc. all fail to remove the rust stains .

If ever I win the lotto the kitchen is top on the list, other wise whom ever gets it (my grand daughter) when I die will have to deal with it, I told my son to just bull doze the entire crappy thing and begin anew .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better