Black Spots in Bathtub.

[gefact]

BLACK SPOTS RESOLVED!!!!
Hi Gang,
I had the same problem and found the answer on another thread. The problem was in the braided lines connecting the hot water heater to the water line. The inside is black rubber and when they get old the insides peel away and release into the water system. I just replaced my hoses and cut one of the old ones opened and the black oily stuff was inside and came off in my finger.

Hope this helps!

[Smoothie]

I have black specks in my bathtub also. They do not spread like mascara. It is more like a hard plastic. It only comes from the hot water heater in my wood furnace. The specks are quite big. You can easily see them and picked them up. They are not metal. Somebody said they had the same problem and they had to replace the mixing valve. What is the mixing valve?

[Angie Scarle]

I also have this problem, but it seems worse than the other people. Sometimes it's big chunks of black in the bathtub like charcoal. I have learned to manage it by keeping the pressure & temperature down. However, if someone flushes the toilet, uses a sink, or anything while I am running bathwater, I get loaded with huge chunks of this black coal like substance in the bathtub. My house was built in 1995, and the black only seems to come out of the master bathtub, and one sink that is right next to it. The bathtub is the most noticable. It's really annoying. I have a weird water heater, it had to be special ordered because of a unique venting system. I don't believe it's the water heater, because it's been going on over a year, and I have never seen it in the kitchen sink, dishwasher, or anywhere else in the house. i don't want to waiste money taking things apart, the plummer said I needed a new water heater, but this doesn't seem logical to me. If it were the water heater, why isn't it coming out of all f the faucets?

[AndE]

I also have this problem, but it seems worse than the other people. Sometimes it's big chunks of black in the bathtub like charcoal. I have learned to manage it by keeping the pressure & temperature down. However, if someone flushes the toilet, uses a sink, or anything while I am running bathwater, I get loaded with huge chunks of this black coal like substance in the bathtub. My house was built in 1995, and the black only seems to come out of the master bathtub, and one sink that is right next to it. The bathtub is the most noticable. It's really annoying. I have a weird water heater, it had to be special ordered because of a unique venting system. I don't believe it's the water heater, because it's been going on over a year, and I have never seen it in the kitchen sink, dishwasher, or anywhere else in the house. i don't want to waiste money taking things apart, the plummer said I needed a new water heater, but this doesn't seem logical to me. If it were the water heater, why isn't it coming out of all f the faucets?

My hot tub (self contained, heated by electricity) has the problem with sticky black dots (that ruins swimsuits, when we wear them!) which suggests it has nothing to do with water heaters/rods, water softeners, copper pipes, etc. It's second-hand, and probably 10 years old. I'm going to check everything rubber next. Thanks plumber buddies for the suggestion!

[hj]

quote; You mean to tell me this problem is so unusual that no one can help

It is NOT an unusual problem. In fact it is very common and is often accompanied by the odor of "rotten eggs". My solution is to remove the anode rod and leave it out. That almost always cures the problem, unless it has deteriorated to the point where it has caused deposits on the bottom of the tank, and if so, it is almost impossible to "flush" them out. And just have to wait until they come out with the water's flow.

[phostis]

Had the same problem as original poster: greasy black spots that smear like mascara.

Solution: Replaced expansion tank. The old one was, repeat WAS, installed correctly on the cold water line. When the plumber pulled the old one off and stuck a screwdriver into the neck it came out covered in greasy black goo.

Plumber said has been working since 1967 and this was the first instance of this he'd ever seen. When he rattled the old tank you could hear the water sloshing where it had penetrated the bladder.

Don't let them tell you you're crazy. This can be fixed.

[julielver]

I have the identical problem. It only occurs in my bathtub upstairs with hot water, and not in the bathtub downstairs. I saw the particles in the vanity sink next to the tub, but that was just once. It only occurs with the hot water. Lots of them come out in big bursts, especially when we haven't used the tub in a few weeks. We have our own well with a big-blue filter on it. We recently changed the filter, still have black specks.
We don't have a water heater, we have a Buderus boiler that heats the hot water. We have a water softener. I have a chemistry background and did some tests on the black stuff. i tested for manganese dioxide and iron, no reaction.I used hydrochloric acid to see if it would dissolve, no reaction, so that would rule out many metals. I used an organic solvent like acetone and lighter fluid. I tried burning the stuff in a spoon on top of the stove. No reaction-the stuff doesn't burn like rubber would. That would rule out rubber, I think. I used a powerful magnet, which would detect iron and nickel, no reaction. The article from Florida indicated that magnesium sulfide water reaction with copper pipes would make copper sulfide, but that mineral is blue, not black. It seems to be a mineral of some type. i was just theorizing that since most of the posts here are from new construction, that possibly the interior of the new tub filler faucets using high water pressure and hot water could be the problem. We have an old house from the 1930's. We recently rehabbed the bathroom. We didn't have the problem before the rehab. We got a new tub filler from Porcher (the high end of American Standard). They have since discontinued this faucet line. Any thoughts about this theory?