What’s the Black Slime Under My Faucet?
April 22, 2025

Whether you're cleaning your sink, washing your hands or brushing your teeth, it’s likely you’ve come across something strange lurking in your faucet – black slime. While it’s alarming, (and unsightly,) it's a naturally occurring phenomenon, commonly found in Georgia homes. So, what is this black gunk and how can you get rid of it?


What Is This Mystery Slime?


Well, it’s actually oxidized manganese. The mineral is found in trace amounts in our water. When manganese comes in contact with air, a chemical reaction called oxidization occurs, making the mineral appear black or brown. Over time, oxidized manganese can build up on shower heads, toilets and faucets. 


Is Oxidized Manganese Dangerous?


While bacteria do feed on the oxidized manganese, they are typically harmless. The mineral itself (although unpleasant looking), is harmless to people and animals in trace amounts. 


Can I Get Rid of Oxidized Manganese To Prevent Slime?


Yes, there are some things that can be done to remove manganese from your water supply. Oxidation and whole-house water softeners can be used if you live on well water. While city water is already treated, you may still have hard water. If that's the case, a water softener may be a good option for your home. 


While it's a more permanent fix for treating black slime, water softeners require sizing, installation and maintenance. Additionally, manganese is found in our state’s groundwater, and trace amounts of it are likely to get into our water supply, according to the
University of Georgia Cooperative Extension.


If you have small amounts of slime buildup (and it doesn’t bother you terribly,) it may be easier to remove the slime with regular cleanings. For some homeowners, occasional flushing of your home’s main system may also keep black slime away (at least for a while.)


How To Clean Oxidized Manganese (Black Slime) From Faucets

  • Oxidized manganese can be removed by gently scrubbing your faucet with a cloth and dish soap (dish soap will remove the slime, but not staining)
  • A combination of vinegar and water may be used to remove the stain (be gentle when applying the mixture, so as not to damage your faucet’s surface)
  • A combination of baking soda and water can also be used to remove staining  (be gentle when applying the mixture, so as not to damage your faucet’s surface)


What Should You Be on the Lookout For?


While black slime is not a health concern, black mold is. Although they look similar, black mold appears dark green or black, while slime can appear brown or black. Mold is also spotted in appearance.


Black mold is a health concern, as its spores can cause allergic reactions in some people. 

The most common symptoms are:

  • Sneezing
  • Runny or stuffy nose
  • Cough and postnasal drip
  • Itchy eyes, nose and throat
  • Watery eyes
  • Dry, scaly skin


For those living with asthma, black mold can be a very serious problem, as the spores trigger asthma attacks which cause coughing, wheezing, shortness of breath and chest tightness. 


If you suspect you have mold growth in your faucet, it's always best to contact a mold removal specialist. They can help remove any mold present within the home.


To prevent mold growth, it's important to keep an eye out for any leaks. While a leaky faucet may seem like a small problem, it can lead to mold growth if left unchecked. Moreover, faulty faucets can cost you lots of money in the long run. A leaking faucet that drips every five seconds can waste an estimated 400 gallons of water per year, adding costs to your monthly water bills.


Leaky Faucet? Superior Plumbing Has Got You Covered!


If you’re a metro Atlanta homeowner looking for an experienced plumber, Superior Plumbing is standing by! Our team of plumbers are able to repair leaky faucets and install new ones when it's time for an upgrade. 


We serve several areas around Atlanta, including Kennesaw and Cobb County. Give us a call at 770-422-7586 or click the link
here to fill out a contact form online. Not only do we perform  routine plumbing services, but we also install water heaters and tankless water heaters. If you’re interested in our other services, visit our website by clicking the link here