Sometimes you notice black specks in your water; you may wonder what they are and if they are safe to drink. If your filtered water contains black particles, it will most probably be carbon, especially if you just installed a new filter. Old or damaged carbon water filters allow manganese or iron particles to pass through, which causes black particles in water.
In water purification, activated carbon removes impurities and contaminants through a chemical adsorption process. However, it is used for many other applications besides water filtration. In fact, activated carbon is an essential ingredient in various industries. Thus, it’s common for you to find carbon dust in your water.
Besides carbon filters, mineral deposits, sand or silt, rust, worn-out rubber parts, and corroded water heaters could be other possible causes of black specks in water. Here is a detailed guide on the carbon dust sources and prevention techniques for black particles or carbon dust.
Sources for Carbon Dust in Water
If you see carbon dust in your filtered water, there could be three possible reasons behind it.
1. Detachment of Carbon Powder from Filter Media
The most likely cause of black specks in filtered water, is carbon particles from the filter media. Some of the carbon in the media may dissolve during the manufacturing and shipping of activated carbon filters. This will introduce black particles into the water supply.
2. Carbon Dust from Brita Filters
Carbon in Brita filters can cause filtered water to turn black. New filters tend to contain loose carbon dust and carbon particles that can get into the filtered water. The black particles in Brita’s filtered water are large chunks of carbon. The carbon in all Brita filters is activated carbon. In the manufacture of activated carbon, carbon is typically exposed to very high temperatures, usually pure gases such as argon or nitrogen.
3. Granular Activated Carbon (GAC)
Most water purification systems use granular activated carbon filters in cartridges to purify water. These particles are more visible, like coffee grounds. This problem can be easily solved by simply replacing the filter cartridge.
Sources of Black Particles in Water
Besides carbon dust, there could be other black particles in your water. These particles enter the water through the following sources.
1. Mineral Deposits
A less likely cause is that the water is black due to impurities. Presumably, water purifiers can only remove specific contaminants, not minerals such as manganese or iron. These minerals are known to give water a black tint when reacting with oxygen.
Black spots can be trace amounts of iron or manganese in the water. While they may look scary, these minerals are generally harmless in small amounts. You can take a water test to find out the mineral content of your water.
2. Sand or Silt
Small pieces of black and brown sand or silt can appear in water from a private well. This water is harmless, but it can cause appliances such as washing machines and dishwashers to wear out faster than normal. Also, water can damage the well pump. Some possible solutions are to let the well run for a few days when it is new, install a screen, or put a liner in the sandstone.
Rust in water usually appears brownish-orange, sometimes even black. These particles come from rusting steel and plumbing pipes in irregular shapes and sizes. If your water constantly releases rust particles, especially cold running water, you should call the water department.
On the other hand, if the problem is caused by hot water in one or two faucets, it will resolve itself after a while. If so, the steel pipe may have rusted. In that case, you should have a plumber check it out before the problem becomes severe over time.
4. Worn Rubber Parts
Collect some black dots on your hand. Do they feel like rubber? In this case, it could be a small piece of rubber on the line. Rubber washers, gaskets, and tubing are used to make waterproof connections, but the material degrades over time. Try replacing the rubber part of the faucet and see if the black spots are still in the water.
5. Corroded Water Heater
If the black spots appear only when you turn on the hot water, you should first look for your water heater. The average lifespan of a water heater is 8-12 years. You can empty the tank and flush the lines if the device is on the new side. However, if your water heater is getting old, it’s a good idea to replace it to avoid major problems and disruptions when it fails.
Prevention of Carbon Dust and Black Particles in Filtered Water
Cleaning the Water Filter
The best way to keep filtered water free of black particles is to follow the manufacturer’s instructions and rinse the water filter before use. Cleaning the filter is easy. Simply soak the filter in water or soak it in cold water for about 5-15 minutes. This allows loose activated carbon particles to escape the filter media and be flushed down the drain.
When installed, the filter should be ready for use and free of loose carbon. Rinsing and soaking the filter allows the water to be used for non-potable purposes, such as drinking water.
Remove Air Bubbles from Water Filter
Filters may contain air bubbles, which leave loose particles on the media. To fix this issue, place the filter in a bucket of cold water and check for trapped air bubbles. Floating filters may have trapped air bubbles. If the filter floats, repeat the soaking and rinsing process.
Soak the filter upright in cold water for up to 15 minutes. Flush the filter with cold water for 20-30 seconds. With the filter upright, tap the side of the sink the filter. This removes trapped activated carbon particles. Place the filter back into the bucket of water. If it still floats, repeat the process until all trapped air bubbles are removed.
Replace Old or Worn Out Rubber Parts
In case you find rubber parts in your water, you must call your plumber. Ask your plumber to inspect the lines and plumbing systems. If he finds old or worn-out rubber parts, ask him to replace them with the new rubber fittings.
Frequently Asked Questions
1. Can activated carbon filters make you sick?
No, carbon filters can’t make you sick. In fact, carbon filters are good for you as they reduce harmful contaminants such as chemicals and disinfection by-products. The only way to get sick with activated carbon filtration is not to replace the filter on time. Old filters are prone to bacteria and mold, which can cause disease.
2. Is the carbon in the water filter safe?
Yes, the carbon in the water filter is safe to drink. The EPA does not regulate carbon, and there is no official Maximum Contamination Level (MCL) for this contaminant.
3. Why is there carbon in my filtered water?
Water purifiers use a special kind of charcoal called “activated carbon” to purify water. Activated carbon works through a process of adsorption. Adsorption chemically binds contaminants to the surface of the activated carbon filter rather than physically absorbing them. That’s why you may find carbon in your filtered water.