This article will address the major health issues and maintenance of the popular, widely relied upon and trusted, carbon water filters.

A carbon water filter is one of the most common types of water purification system used in homes. Although effective for removing many harmful substances, they have a number of disadvantages effecting the quality and chemistry of the filtered water that I will cover later, but first …

There are several major reasons why carbon water filters are the number one choice for cleaning up the tap water nationwide.

Aggressive marketing as a result of low manufacturing costs and extremely high profits.

The creation of false insurances regarding their effectiveness

Carbon filters do remove many chemical and cancer-causing substances and are reliably inexpensive compared to reverse osmosis, deionization and distillation and since there is a very high profit margin, this method of water purification is preferred. Unfortunately, many of the manufacturers and / or salespeople, are not forthcoming in what a carbon will can and can not do. Instead of mentioning what it can not do, the will amplify and exaggerate the positive aspects of the filter. As a result the consumer is under the false impression that their “filtered water” is now healthy.

Carbon filters are not complicated and are there easy to install.

Most people are looking for simplicity at a great price

It is not a secret that most municipal water supplies are polluted to some degree, however, the average person is unaware of any of the details or facts about these pollutants or what is involved in removing all of them from the water. If they are told that a carbon filter removes dangerous substances and it does so cheaper than any other method and the water will taste and smell better, that's good enough for most people.

Carbon filters do indeed remove many dangerous chemicals and carcinogens

What about the harmful toxins and substances filters do not remove?

Activated carbon filtration systems do not remove microbes, sodium, nitrates, fluoride, hardness, inorganic, minerals that create kidney and gall stones, lead and other heavy metals.

The activated carbon removals most of the bad tastes and smells

Our sense of sight, smell and taste can be easily and flatly deceived!

In case you are unaware, most of the dangerous chemicals and substances found in tap water are colorless, odorless and tasteless. As a consequence, most people do not get concerned as long as their water taste ok, smells OK and looks clear.

Most filter systems use replaceable cartridges that are easy to replace

It is not a matter of how easy a filter can be changed, but rather when to change it.

Most contaminants in water are measured in Part Per Million (PPM) and as these chemicals pass through the filter they are attracted and absorbed by the carbon. As a result, they begin to accumulate in larger quantities than what might be safe levels according to the Environmental Protection Agency (EPA) Not knowing at what point the filter is full or holding all the chemicals it can, larger quantities of chemical than are found can easily be forced loose by the pressure of the water passing by. Changing the allowed PPM of certain chemicals to high concentrated levels released into your glass.

Clogging and Channeling

Carbon filters will clog in many places, forcing the water to go around the clog. This process continues until an unobstructed path through the filter is found. This process is called channeling. Channeling provides an unrestricted flow for the water and pollutants to pass through the filter, totally negating the carbons ability to retain the pollutants. Without there was a dramatic change in the filters flow, you would not know there was a serious problem, nor when to change the filter.

Rate of Flow, Water Pressure Affect the Filters Performance

Case in Point: The most ineffective water filter on the market is the small one that attaches to your faucet spout and you push a button for the water to flow through it. The main requirement of a carbon filter is that it needs to be of a size proportionate to the volume of water, rate of flow and water pressure to allow the suspended pollutants to stay in contact long enough for the carbon to attract and absorb them. That little tiny filter does not contain enough carbon for this to happen. The water shifts through in a fraction of a second, giving up nothing to the carbon it passed.

Breeding Ground For Molds and Bacteria

Another disadvantage of a carbon water filter is that it is susceptible to mold. The organic substances that are captured by the filter are capable of rotting after being trapped. Therefore, if you leave the carbon water filter unused for prolonged periods, mold will likely grow inside of it. In addition to mold, a filter can be a breeding ground for bacteria.

In Conclusion: The volume of carbon needs to be in direct proportion to the volume of water that it is expected to filter. Carbon filters are best used as pre-filters and post-filters for more reliable purification methods:

  • Distillation
  • Deionization
  • Reverse osmosis

Why leave anything that is not needed by your body in the water? Take everything out! You spend hundreds on a computer or TV which does nothing for your health or longevity, spend a few bucks on attaining good, clean, pure, clear, healthy H2O.


Many people have water that is too acidic. Unfortunately, a carbon water filter can not change the pH balance of the water. The minerals that cause acidity in the water dissolve and pass right through the filter. So if you have acidic water, it will still be acidic after going through the carbon water filter.


In addition to being susceptible to mold, they are also sentenced to clogs.


Clogs are yet another disadvantage of a carbon water filter. Undissolved solids usually clog up the filter. These clogs will reduce the normal lifetime of the filter. If your water has a sediment problem, you will probably have to use a separate sediment prefilter to keep clogs from ruining your carbon water filter.

Harmful substances

One of the last disadvantages of a carbon water filter is that they do not remove certain harmful substances from your water. The filter will do nothing to get rid of harmful nitrates or toxic metals that contaminate the water. Also, a carbon water filter is incapable of removing high levels of sodium and fluoride.

These are some of the disadvantages of a carbon water filter. The system requires frequent filter replacement because it will lose its efficiency over time. This type of water filter is also incapable of changing the pH balance of the water and getting rid of certain harmful substances. Also, a carbon water filter is unacceptable to clogs and mold if they are left unused for a long period of time.