We have a resort rental house at a large lake in MD. The water supply contains both rust & coal sludge at times. I have a sock water filter in line. The black sludge does build up in the toilet tanks however.
The dishwasher walls and baskets used to have this baked on black stain. It looked like we never cleaned our dishwasher. I thought for over a year it was from greasy pans the renters put in dishwasher with out rincing first!
We tried for many moths to clean it. Every thing by a neuclar blast would not move the stain. Tried alcohol, bleach,amonia, on & on. THe only thing that was close to taking it off was barbaque cleaner, but even then every basket prong had to be forceably pulled to clean it.
The real solution was putting "Tang" in the place for dish powder & just let it run the cleaning cycle. I could not believe it!!!
