Written by: Alexandra Uta // Last Updated: Apr 19, 2023
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If your whole house water filter has turned black, it’s not usually something to worry about. However, it’s always safer to assume it’s a serious concern, as harmful contaminants may be involved.
Depending on the severity, you may need to call a professional or replace your whole house water filter – but knowing why it has turned black in the first place can help you decide what to do next.
In this guide, we will discuss the different causes for a whole house water filter turning black and how to find the culprit. Let’s get started!
Key Takeaways
If you whole house water filter turns black:
There are many factors to why your whole house water turned black. Consider the following:
One of the most common causes for a whole house water filter turning black is iron or rust in your water. This can be due to old pipes in your home or well water that contains high levels of iron.
Manganese is another common cause of black water filters. Like iron, it can be present in well water. High concentrations of manganese may be harmful as it could lead to health problems.
If you are dealing with well water, you may have black sediment problems. Black sediment could either be these two things:
For well water, it is common for there to be sand and silt since the water runs over rocks and soil. This can build up over time and cause your filter to turn black. Sand and silt are not particularly harmful, but they can decrease your water quality.
Sometimes organic matter, like algae or bacteria, may find its way into your well water and decompose. Over time, this could clog up your pipes and whole house water filter and cause the water to appear dirty/black.
If your whole house water filter uses activated carbon, the black color is most likely due to the carbon itself and is not a cause for concern. Over time, the carbon will become saturated with impurities and will need to be replaced.
Black water filters are sometimes accompanied by a musty smell. If that’s the case for you, it could be due to mold or mildew growth caused by high humidity levels or a lack of ventilation in your home.
Newly dug wells can make your water appear dirty or discolored for a while. The black particles could be minerals or sediments that have been drilled up during your well’s construction. It may be a while for these particles to clear up, but they are not a serious matter.
Heavy rain or an earthquake may cause your well to collapse, which can allow sediment and other contaminants to enter your water supply. This can clog your whole house water filter and turn it black.
A failing septic system can also cause your whole house water filter to turn black. The septic tank can leak sewage into the groundwater, which will then be filtered through your whole house water filter.
To ensure fewer instances where your whole house filter turns black, it’s best to address the root causes. Here are things you can do to find the culprit:
A good first move to figure out the culprit is to get your water tested. There are different types of water tests, but you’ll want to specifically test for iron and manganese. These minerals are often the culprits behind black water filters.
You can either have a professional come out and test your water, or you can purchase a do-it-yourself testing kit from a hardware store.
Check your pipes and water heater for any signs of corrosion. Since pipes are usually constructed with iron, they may rust or corrode over time. Make sure to have them inspected and repaired if needed.
If you have a carbon filter as part of your whole house water filtration system, then it’s possible that the filter just needs to be replaced. To check, take a look at your carbon filter and see if it’s leaking filter media or if there’s a lot of build-up on it. If so, then it’s time for a new filter.
If you have a well, check to see if the water level has lowered. This could be a sign that your well is running low on water and causing sediments to enter your home’s water supply.
A malfunctioning septic system can release contaminants into your water supply, which will turn your whole house water filter black. You should have your septic system checked by a professional at least once a year to ensure that it is functioning properly.
The best thing to do when your whole house water filter turns black is to replace it. That way, your water quality may improve, and you can prevent any health hazards. But if you have successfully determined the cause to be not harmful, here are a few things you can do to help maintain your whole house water filter:
In some cases, your whole house water filter turning black may be unavoidable. But there are measures you can take to ensure these instances don’t happen as frequently.
With these precautions in place, you will be far less likely to encounter a blackened and dangerous whole house filter.
If you have any questions about why your whole house water filter gets black please don’t hesitate to leave a comment below!
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