Water Filters: What They Really Remove

When you buy a water filter, the product description usually lists an impressive list of contaminants it claims to remove. In many cases, the list is accurate, but in others, it is exaggerated or general. The question that is of fundamental importance to every consumer is what substances a water filter actually removes in your own home, with your own mains pressure and with your own incoming water quality.

In today's guide, we break the list into two categories: what is actually removed by a quality filter, and what remains in the water even after filtration, unless you choose more specialized technology.

Five Categories of Pollutants That Are Actually Removed

Chlorine and Chlorination Byproducts

Chlorine is the first substance that almost every water filter effectively treats, thanks to activated carbon. The adsorption technology binds both free chlorine and its secondary products, such as trihalomethanes. In practice, this translates into an immediate improvement in taste and odor. In Olympus Plus antimicrobial water filter The activated carbon is combined with a ceramic element, doubling the total filtration surface.

Heavy Metals

This category includes lead, cadmium, mercury, hexavalent chromium and arsenic. These are metals that can enter the water from old pipes or natural sources in the area. Quality home filters retain them thanks to layers of special filtering materials. According to data from European Chemicals Agency ECHA, long-term exposure to heavy metals through drinking water is a public health issue, particularly in areas with old plumbing networks.

Solid Particles, Sediment and Rust

When you turn on the tap after a water outage or in old pipes, cloudiness and fine brown particles come from turbulence in the pipes. A ceramic filter combined with 0.5 micron microfiltration retains these solids both for visual clarity and to prevent them from ending up in electrical appliances that use water, such as coffee makers and kettles.

Pesticides and Industrial Organic Pollutants

In rural areas or near crops, some pesticides can reach drinking water through surface runoff or groundwater aquifers. Activated carbon effectively adsorbs a wide range of organic pollutants, including some pesticides. The efficiency depends on the concentration and chemical nature of each compound.

Pathogenic Microorganisms

In the filter chamber, where water remains for some time between uses, microorganisms can grow. In the Olympus Plus series, the inner surface of the chamber utilizes an antimicrobial copper alloy. The technology has been tested by the Microbiology Laboratory of the Medical School of the National and Kapodistrian University of Athens and neutralizes up to 95% of microbes inside the device in 2 hours. In addition to microbial protection in the chamber, the ceramic element also retains bacteria at the level of mechanical filtration.

What a Common Filter Does NOT Remove

This is where many consumers are surprised. A conventional activated carbon and ceramic filter, even a high-quality one, has certain limits.

Salts and Water Hardness

When a white scale forms on your kettle, it is calcium and magnesium. They are not dangerous to your health, but they affect the quality of food, the taste of drinks and the lifespan of electrical appliances. A regular water filter will not remove them. To reduce them, you need an Olympus double or triple water filter or a water softener or a reverse osmosis system.

Nitrates

Nitrates are small ions that are not retained by activated carbon or ceramic. In areas with elevated nitrates due to agricultural activity, the only domestic solution is reverse osmosis or a specialized ion exchange filter. In the Olympus Plus series, the double and triple filters with a special stage for nitrates, marked with red or white screw color.

Fluorine

In some areas of Cyprus, the natural fluoride content of water may be higher than desired. Activated carbon does not effectively bind fluoride. The specialized solution is a reverse osmosis device, which removes it almost entirely.

Pharmaceutical Residues and New Pollutants

Newer studies, such as those monitored by the European Food Safety Authority (EFSA), detect pharmaceutical residues and trace hormones in drinking water. Dealing with them goes beyond the capabilities of a conventional filter. This requires either advanced activated carbon technology of a specific quality, or reverse osmosis systems.

How Efficiency Changes Depending on Technology

The same substance can be filtered differently depending on the technology. Below at a general level:

• Olympus above/below counter antimicrobial filter Plus: Chlorine very well. Heavy metals very well. Particles at 0.5 micron. Microbes in the chamber up to 95% in 2 hours. Calcium & magnesium salts or Nitrates with special stage in double/triple models.
• Reverse Osmosis: Almost completely free of contaminants, including nitrates, salts, fluoride, pharmaceutical residues.
• Central supply filter: Broad protection of the whole house, but less specialized at the final point of consumption.

How to Confirm What Your Filter Really Does

Before accepting any claim of filter effectiveness, look for three things. First, independent laboratory tests. In Olympus Plus filters, the effectiveness has been confirmed by the Agricultural University of Athens with a bacteria retention study and by the Microbiology Laboratory of the Medical School of the National University of Athens. Second, clear specifications: which substances, in what concentration, in what amount of water. A vague claim about «cleaner water» is not documentation. Third, the quality of the network in your area. You can request data from Cyprus Water Development Department or local water authorities.

All water filters in the Olympus Plus series are manufactured in Greece by the company Center Plus, have a registered Greek patent and a 2-year warranty, with one cartridge covering 12 months or 8,000 or 14,000 liters of water. .

Frequently asked questions

Do All Water Filters Remove the Same Substances?;

No. Different technologies have different targets. Activated carbon is ideal for chlorine and organic pollutants, while reverse osmosis covers almost the entire spectrum of pollutants. The choice depends on the actual needs of your home.

Does the Filter Remove Salts from the Water?;

A single antimicrobial filter does not reduce water hardness. However, in the Olympus Plus series there are double and triple models with a special stage for salts. Also, salts are retained by a softener or a reverse osmosis system. 

How Effective Is a Heavy Metal Filter?;

A quality filter with a ceramic element and activated carbon removes heavy metals to a high degree. The exact performance depends on the construction, materials and concentration of metals in the incoming water.

Do Filters Remove Pharmaceutical Residues?;

Only specialized technologies, such as reverse osmosis or advanced large-surface activated carbon, can effectively reduce pharmaceutical residues. Conventional filters are not sufficient for this category.

How Do I Know If I Need Reverse Osmosis?;

If your area has elevated nitrates, high hardness, brackish water or undesirable levels of fluoride, reverse osmosis is warranted. In urban areas with water within normal limits, an antimicrobial filter usually covers all needs. See the options in detail on the page of Olympus Plus water filters and contact us for a personalized proposal depending on your consumption profile and your region in Cyprus.