I live in an apartment building that was constructed in the early 1970s. We
have hot water heating (baseboard), and I have no idea if the boiler is the
original, or what. But, hot water from the tap is always slightly
discolored, like diluted tea. Obviously, nobody drinks it, but we shower in
it, and it runs through the dishwasher and clothes washer. And, it leaves
deposits on things like the white rubber dish kitchen sink drainer mat.
By the way, it doesn't matter how long I let the water run or what time of
day - the color is always the same.
Anyone know what potential kinds of crap might be present in a very old hot