What material is found in most home water filters? Activated carbon. And what is the most inaccurate information circulating? The same.

An activated carbon filter is sometimes presented as cleaning everything and sometimes as simply flavoring the water. Below we take five common perceptions one by one and see what is true in each, based on how the material works.

First, How Activated Charcoal Works

Activated carbon cleans with adsorption, not by sieving. Substances are not stopped because they are too big to pass through, but because they stick to its surface and stay there.

It is carbon that has been specially treated to fill tiny pores. Each pore offers new surface area where molecules bind, which is why a small filter processes hundreds or even thousands of liters before becoming saturated.

However, the binding is selective. Carbon has a chemical affinity for the organic compounds and with it chlorine, that is, with the substances that make up the taste and smell. It does not have the same relationship with dissolved inorganic salts. From this distinction arises everything that follows.

An activated carbon filter rarely works alone. In home appliances, it is combined with other stages, each of which takes on a different part of the job. See how it is applied in Olympus water filters per type of installation.

Myth 1: "Water Cleans Everything"«

It is not true. An activated carbon filter works very well on one family of substances and not at all on another. The line is chemical and does not move with marketing.

The remainder belongs to him. chlorine of the network, along with some of the byproducts it creates when it reacts with organic matter in the pipes. They also include organic compounds, from substances of agricultural origin to compounds that come from the piping materials themselves. And the smells with flavors, which almost always come from organic molecules in very small concentrations.

Out of range are: nitrates, which pass practically unaffected by coal. It is measured in areas with intense agricultural activity, and requires another arrangement, such as the double and triple filters  or the reverse osmosis filter that retain nitrates. The heavy metals They are sometimes partially bound and sometimes not at all, depending on their chemical form, so they are not a systematic solution. More about the heavy metals in water.

The European Directive 2020/2184 sets limits for each of these parameters separately, because no technology covers them all together.

Myth 2: "It Softens Water and Dissolves Salts"«

It is not true, and it is the most common disappointment. Hardness is due to dissolved calcium and magnesium salts, which activated carbon does not touch at all.

If you see scale in your kettle, tiles or glasses, a carbon filter is not going to stop it. It is a different problem and requires a different solution. See what applies to water hardness by region. Center Plus with Olympus water filters has filters that are capable of retaining calcium and magnesium salts

The same applies to sterilization. Activated carbon does not kill bacteria. A saturated and permanently wet filter can even encourage their growth within the device itself. This is precisely what the Olympus antimicrobial filters, where the inner chamber self-disinfects on a permanent basis and up to 95% of microbes inside the device are neutralized in 2 hours.

Myth 3: "If the Water Comes Out Clear, the Filter Is Working"«

Dangerous perception. The duration of an activated carbon filter is measured in liters or even months of use and Exhaustion is nowhere to be seen.. It is the point where most of the performance is lost in practice.

When the carbon surface is full, the filter stops binding and the water passes through essentially untreated. The flow remains the same. The appearance of the water remains the same. You usually only realize this when the chlorine taste returns, which is after some time has passed.

Therefore, the manufacturer's limit is binding and not indicative. In Olympus thermos bottle the filter filters up to 300 liters of water, approximately 400 fills, and then it is replaced.

Practical instructions per model are available at water filter maintenance guide.

Myth 4: «All Carbon Filters Do the Same Job»

Only partially. Two devices can both claim to have an activated carbon filter and give very different results. The principle is the same, the performance depends on the type of carbon, the contact time with the water and what else is inside the device.

Contact time is the most misunderstood factor. The faster the water passes through, the less it binds. 

The combination also plays a role. When carbon works together with a mechanical retention medium, such as the ceramic filter found in Olympus water filters or even the polypropylene found in many filters on the market, the device retains additional dust, rust, and sediment from old pipes. This is not adsorption, it is mechanical filtration, but in practice the two work together.

Myth 5: "If the Water Is Potable, the Filter Is Superfluous"«

It depends on what you expect. Potable and enjoyable are not the same thing. An activated carbon filter does not make water that is already safe safer, it works on the second leg.

In large urban networks, water is systematically tested and the results are published. You can see the data for EYDAP water quality and compare them with your area. If the microbiological and chemical parameters are within limits and you are only bothered by the taste, activated carbon does the job it needs to do and nothing more.

Something more is needed in three cases: when there is a confirmed microbiological issue, when analyses show elevated nitrates or salts, and when the supply does not come from a controlled network. European Environment Agency monitors these pressures in European waters.

If you don't know where you belong, guide to selecting the right filter guides you based on the water in your area. Also useful is the What you need to know about water filters.

The Same Coal, Outside the Home

The technology is not limited to the kitchen faucet. It works on any size faucet, as long as there is sufficient contact time with the water.

The thermos bottle with activated carbon filter applies the same principle in portable form. Capacity 740 ml, body from stainless steel 304, net weight 395 g, and the filter is inside the straw, so the water is filtered the moment you drink it. Before first use, it is activated by submerging in water for 10 minutes.

For optimal filter performance, the water temperature should not exceed 60°C. That is, the device is intended for water, not beverages. The replacement filter is sold separately, so the bottle does not end in the first 300 liters.

Center Plus SA supplies you with the thermos bottle with 2 years warranty and technical support. Available in green and white, in category Thermos Bottle with Filter.

Frequently asked questions

Does the activated carbon filter remove chlorine from water?;

Yes. Chlorine and the compounds it creates are among the substances that an activated carbon filter has the greatest affinity for. It is its primary and most noticeable job, and it is visible from day one.

Does it remove salts and soften water?;

No. Dissolved calcium and magnesium salts pass through unaffected. Hardness requires a different technology.

How often should I change the filter?;

Based on the liters specified by the manufacturer, not by eye. In the Olympus thermos bottle the limit is up to 300 liters or about 400 fills. Exhaustion does not give a visible sign.

How much does the replacement filter cost?;

The replacement activated carbon filter for the thermos bottle costs 9,00 €. With a duration of up to 300 liters, the filtration cost is three euro cents per liter.

Is ceramic filter better than activated carbon?;

It's different. Ceramic works mechanically, with very small pores that stop particles. Carbon works chemically, with adsorption. In serious devices they coexist, because they cover different things.

Where We End Up

Of the five myths, four are debunked, and the fifth depends on what you're looking for. Activated carbon fixes the taste, odor, and organic load. It doesn't soften, it doesn't sterilize, it doesn't remove nitrates, and anyone who promises otherwise is describing something else.

Within these limits, an activated carbon filter works reliably, cheaply, and without complicated installation. All it asks is that you change it on time, because when it's exhausted, it doesn't warn anyone.

See the entire series at Olympus water filters and choose based on the water in your area.

John Giotis

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