Black Brita Filter Water – What Is It And Is It Harmful?

If your Brita filter water is black or has black particles in it, you’re not alone! Black filter water is not nice to look at or drink, and you may be wondering if it’s harmful. Here are the reasons why your Brita filter water is black and what you can do to fix the problem.

Brita filter water may be black or have black sediment due to carbon dust or carbon particles coming from the filter. Inadequate pre-soaking and flushing of your Brita filter, or air bubbles trapped in the filter, can cause your Brita filter water to turn black.

Black stuff in your water filter is never a good feeling. In this post I explain where the black bits in filtered water is coming from, how to pre-soak and flush filters properly, and also what else can cause filtered water to go black.

Why Is My Brita Filter Water Black?

There are five different types of Brita filters. While the filtration method varies between each Brita filter, they all contain some form of activated carbon:

  • Standard – Granular Activated Carbon (GAC)
  • EliteTM Proprietary active filtering agents (mainly activated carbon)
  • Stream – Proprietary dual-layer carbon form
  • Bottle – Carbon block form
  • Faucet – Tightly bound carbon block

The carbon in Brita filters can cause the filtered water to turn black. New filters are especially prone to containing loose carbon dust and carbon particles that can enter your filtered water. Black particles in your Brita filter water are just larger sized carbon pieces.

The carbon in all Brita filters is what’s called activated carbon. Manufacturing activated carbon typically involves exposing carbon to very high temperatures and usually some form of pure gas, such as argon or nitrogen.

The purpose of creating activated carbon is to massively increase the number and density of carbon pore spaces. Carbon activation creates a micoporous structure containing numerous “active” sites, where contaminants in water (or air) can be adsorbed.

As you can probably imagine, this microporous carbon structure can also contain some loose carbon. This is the source of the black stuff (black bits) you find in Brita Filter water.

Carbon filters of all types – not just Brita – usually require pre-soaking and flushing before use to get rid of any loose carbon and ensure no air bubbles are trapped inside.

Inadequate preparation of your carbon filter reduces its ability to remove contaminants plus you can end up with carbon in your filtered drinking water.

Is Carbon From Brita Filters Harmful?

Consuming activated carbon dust or particles from Brita filters is not harmful. Carbon is not regulated by the EPA, and there is no standard maximum amount that you can’t consume.

In fact, some people believe that consuming activated charcoal (carbon) has positive health benefits such as blood cleansing, teeth whitening, and reduced flatulence and bloating. While none of these claims have been proven, or supported by scientific research, there are many activated charcoal (carbon) products that are regularly consumed by the public.

These activated charcoal (carbon) “health” products are ingested at much higher concentrations than what you are probably consuming in your filtered water.

There is, however, a very slim possibility that activated carbon in your stomach COULD adsorb some beneficial substances, such as prescription medications or water-soluble vitamins like vitamin C. However, there are no studies that support this, and it is unlikely that ingesting carbon at such low quantities from filtered water would be of any real concern.

So, it’s perfectly ok to drink the carbon from water filters!

Other Minerals That Make Water Black

Apart from carbon, minerals such as manganese and iron in your tap water can appear as small black particles or give the water a blackish tinge.

Typically, these minerals are in oxide form, which means they have reacted with oxygen and can make them appear black. Most people associate iron oxide with rust, which appears as a red or orange color in water, but it can also look black.

If you can see black particles in your tap water, before passing through a filter, then it’s probably just manganese or iron. These minerals are harmless to ingest, but they do make the water less aesthetically pleasing to look at and drink.

If you get black particles in your filtered water, then you are probably just seeing carbon, especially if you have just installed a new filter.

Old or damaged carbon water filter can also let manganese or iron particles through.

The Brita Standard filter uses GAC, which are much larger carbon particle sizes than carbon block filters used in other Brita filters. Also, GAC is prone to forming channels between the large carbon particles, which can could also increase the chance of manganese or iron particles passing through.

You may also start to see these mineral deposits in your filtered water if the carbon filter is reaching the end of it’s expected lifespan or it becomes damaged. Basically, as the filter gets old it can start to let impurities through – time to replace your water filter!

The EPA’s Maximum Contaminant Level Secondary Drinking Water Regulation for Manganese and Iron are:

  • Manganese = 0.05 mg/L
  • Iron = 0.02 mg/L

Can A Brita Filter Get Moldy?

Mold can begin to grow on Brita filters and on the edges of the water chamber. Black mold is toxic to humans and should be immediately removed and the filter system sanitized.

Importantly, mold does not grow underwater as it requires oxygen to grow. This means that mold, including black mold, will not cause the water in your Brita filter to turn black.

While you could get some mold growth on the filter or in the water chamber you won’t get mold growing IN the water.

To avoid mold growth, it’s important to regularly change the water filter and clean the filter system each time you do. Here’s a summary of how often each type of Brita filter should be changed:

Brita Filter TypeReplace Filter After
Brita Standard Filter2 months (40 gallons)
Brita EliteTM Filter6 months (120 gallons)
Brita Stream Filter2 months (40 gallons)
Brita Bottle2 months (40 gallons)
Brita Faucet4 months (94 – 100 gallons)

How To Pre-Soak and Flush Water Filters

All Brita filters must be flushed before first use to avoid getting carbon in your drinking water. Flushing (and pre-soaking) also improves filter speeds and ensures your filter works the way it is supposed to.

It’s really easy to flush a Brita filter and it’s definitely worth doing.

For a Brita faucet filter

  1. Turn the Brita faucet on for at least five minutes after installing your new filter.
  2. Discard this water in the sink or give it to your plants.

Note: Brita faucet filters do not need pre-soaking before flushing.

For Standard, Elite, Stream, and Bottle filters

  1. Pre-soak the filter in cold water for a minimum of 15 minutes.
  2. Then flush the filter under running water for 20 seconds.
  3. With the filter installed, fill the reservoir/bottle completely by letting the water drain through.
  4. Discard this first flush of water.
  5. Repeat this at least two times and discard the water each time.
  6. You may notice the carbon dust on the surface of the water or sticking to the side of the water chamber in the first few fillings – wash out the water chamber under running water to remove any obvious carbon pieces.

Reasons why carbon keeps coming out of your Brita filter after washing

While each type of Brita filter requires some type of pre-soaking and/or flushing (see above) to get rid of loose carbon, you may still get some carbon in your filtered water. Here’s why and what you can do to fix it.

1. Bubbles trapped in the filter

Sometimes, air bubbles trapped in the filter can also cause any lose carbon to remain inside. Even if you have pre-soaked and flushed your filter, you should still check to see if there are any trapped bubbles.

Place the filter in a water-filled sink or bucket and if the filter floats it means there are probably bubbles still trapped.

Getting rid of air bubbles is easy:

  1. Submerge the filter in cold water in an upright position for 15-20 minutes.
    • Rinse under running cold water for 20-30 seconds and reinstall the filter.
  2. If your filter still floats, hold the filter in an upright position and gently tap the filter on the side of the sink, container, or against your hand. This should release any trapped bubbles. Repeat until the filter doesn’t float and then reinstall the filter.

2. Flushing with aerated water

Many faucets have an aerator attached and you can end up putting more air bubbles into the filter than what you are flushing out. To stop this from happening, simply reduce the water pressure by turning the tap slightly lower until there is a continuous (non-aerated) flow of water.

The Bottom Line

Carbon dust and particles from Brita filters can turn the water black or leave behind black bits in your filtered water. This carbon is harmless to ingest but is easily fixed through correct pre-soaking and flushing of your Brita filters.

Russell Singleton

Russell has a Bachelor of Science (Environmental and Marine Geoscience) with Class I Honors. He is currently completing his doctorate in science and is passionate about all earth processes, especially isotope geochemistry and paleohydrology.

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