YAPT: What's this black gunk all up my pipes?

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Diamond Member
Oct 23, 2012
Yep, plumbing...you know a certain percentage of ATOT just got hard as a diamond mine.

Pretty basic, though. My old water heater finally crapped out...had rust on the outside of it for years, but is was just some slow seeping. Today, however, I finally got a puddle.

Got the bog standard unit from Home Depot for $228 $248. Goddamn online price difference bullshit, HOW DOES IT COST YOU MORE FOR ME TO LUG THE MOTHERFUCKER ALL THE WAY FROM THE SHELF TO MY CAR?! 'Sorry, you only save $20 if you pay over the internet and pick it up at the curb.' Putting a price on something and writing 'Pick up in store!' below it, then not honoring that price, should constitute advertising fraud. Oops, wrong thread...

...anyway. I went ahead and reused the existing hookups. Had those copper (or some coppery alloy) bendy pipes (very technical when it comes to plumbing). Before I put them on the new heater, I stuck my finger up in them to make sure there were no burrs or old o-rings or sealer of whatever to fuck me up. It is, of course, just habit to shove my fingers into questionable holes.

Finger came out black. Like, entirely super-duper black. Pic incoming...

[edit to change title from 'YABT' to 'YAPT.' Dunno what happened there. Sorry fellas, this one's not about my butt.]
Hahaha... same thing happened to me. I just walked out and bought it from sears. I also bought the $600 energy star 12year bla bla bla one. But guess they wanted to lose that sale because of $25 or so difference between online and instore. Same heater, part #, and all.

F__K HD.

Oh and get a sacrificial rod to add to your tank. The cheap ones have a very small/weak one.


Jun 13, 2000
You could fill a swimming pool and the stuff would still be there. The magnesium in solution in the water is attracted to the copper piping.

I still like the idea of a whole house filter under the kitchen sink to filter anything that makes it through the system. For the typical daily volume of water that passes through most home pipe systems, it'd flush out most standing water in the lines after someone takes a shower and flushes a few toilets. The filter is more of a catch-all backup that should be the closest to the point of use as possible.


Nov 21, 2001
It is common and is caused by chemical reactions in the piping to treatment chemicals, fine sediment, etc.
I worked on the pipes out in the street and you'd be amazed or disgusted or both at what I have seen.
You'll see a crew out now and then with a hose hooked to a hydrant. They are flushing the lines. After they do that it is a good idea to run the outside faucet a while before doing anything in the house.