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What Makes My Water Filter Turn Black? (Or Specks in Your Water)

We are so used to opening our taps and getting clear, odorless, and clean water – so much so that getting black specks in water almost seems far-fetched. But this is one of the common problems with water filters you might just encounter it in your home.

Water filters turn black because of a buildup of dirt, debris, impurities, iron, and other heavy metals or physical contaminants that get trapped in the filter media. Activated Carbon filters can also appear black before use. Water filters should be changed once they have filtered a set amount of water or after a certain amount of time in use, according to the manufacturer.

The black color in your water filter is directly related to the type of filtration media (material) used in your filter. Most water filters are made of activated carbon which is black. Small carbon particles may flow with water and get trapped in the cartridge giving it a black appearance.

No need to panic, though – it can be managed and fixed quite easily.

What is the black stuff in your water filter?

Granular Activated Carbon(GAC) Granular activated carbon filters employ granules loosely packed to allow water to pass through easily. These filters are not limiting and can allow water to pass through at a fast rate.

The carbon particles for this filter are more likely to flow out with the water and get stuck on the cartridge wall. This will make your water filter look black.

Unlike GAC filters, carbon block filters use fine-ground carbon granules compressed into a block. The filter can also use a bonding agent to hold the granules together. Water flows at a slower rate with carbon block filters. You may notice a faint black color on the cartridge, but it will take more time than the GAC filter.

If you purchase a carbon filter, you will likely find black specks in your water. Your filter is not faulty. The black specks are carbon are loose carbon particles that flow with the water. You can manage this situation by flushing your filter several times until all loose carbon particles wash off. You can also pre-soak your filter before installing it in your system.

At times, you may find your water having black speck after pre-soaking and flushing.

The black specks are caused by:

  1. Your filter might be having bubbles trapped inside. The air trapped inside retains carbon dust. To be sure of this, place your filter vertically in a bucket of water. If it floats, try hitting it gently against your palm or bucket to release the air trapped. Be careful not to damage your filter. Your filter should sink when all the air comes out.
  2. You might be flushing your filter with aerated water. Some manufacturers include inbuilt aerators in filters. It would help if you reduced the pressure of your water. This way, only non-aerated water flushes through your filter.

What are the Black Particles in My Water After Filtering?

Sometimes you may wake up in the middle of the night for a glass of water and find black particles. You have invested in a filter. “So, why are there black particles in my filtered water?” you ask yourself.

Here are the most common reasons for black particles in your water:

  • Mineral deposits
  • Corroded pipes
  • Carbon filters
  • Rubber parts

Mineral deposits

If you live in an area where water has high Iron and Manganese content, you are likely to encounter this problem. Your water is also expected to develop an odor. Manganese is harmful to the body if ingested in large quantities. It would be best to regularly clean or replace filters to avoid this situation.

Corroded pipes

If you are using Iron pipes, your water may turn black when rust starts forming on them. When Iron is oxidized, it turns black or brown depending on the n state of your piping. Your filter may let small particles pass with the flowing water. It would help to get a licensed plumber for inspection and repairs.

Carbon filters

Carbon filters can also cause black specks in your filtered water. If your filter is new, carbon dust might flow out with the filtered water. However, the carbon in the water is not harmful to your body. Consider flushing or pre-soaking your filters before installing.

Rubber parts

Try feeling the texture of the particles with your fingers if possible. Do they feel like rubber? If so, this might be caused by worn-out rubber gaskets and hoses in your plumbing system.

Is Carbon from Water Filter Bad for You?

Luckily you do not have to worry about ingesting the activated carbon in your water filter since it is not harmful. The activated carbon is charcoal made from coconut shells or coal, which are organic materials. Doctors use carbon tablets to counteract toxins caused by food poisoning.

The only problem with carbon is making your water look bad.

Can a Dirty Water Filter Make You Sick?

Yes, a dirty water filter might be harboring harmful bacteria and contaminants. If your water starts tasting funny or developing a foul smell, it is probably time to replace your filters. Giardia lamblia, cryptosporidium, and Vibrio cholera are some microorganisms that might lurk in your dirty filter.

If the filter membrane of your dirty filter is damaged, you might be exposing yourself to heavy metals like lead. Continued use of water with lead can result in health complications. Always replace your filters once they become dirty or old.

What does a bad water filter look like?

Inspecting a water filter before using it can help you avoid consuming unsafe water. Your filter might be faulty. Here are some things you should look out for;

  • Dampness. A damp filter could be harboring bacteria and mold
  • Damaged or torn filter membranes. If the filter membrane is torn, contaminants can pass through.
  • You can tell if your filter is bad by smelling. If it has a fishy or foul smell, consider discarding it for a new one.

The majority of filters in the market employ carbon as the filtration media. It is a relatively cheap and efficient method of water filtration. If your water has black specks, it is probably the carbon found in your filter. Luckily, this carbon does not pose any threat to your health.

New carbon filters are more likely to release carbon dust into your water. Pre-soaking and flushing can help get rid of the loose carbon in your filter.