An activated carbon filter works with a highly porous material, on the surface of which certain substances in the water are fixed. The process is called adsorption. This way, chlorine and compounds that give the water taste and smell remain in the filter.
In the Olympus range, activated carbon appears together with other materials: with a ceramic filter in the kitchen filters, with a copper alloy in the shower filter, and in the thermos bottle it is part of a polypropylene filter. Each cartridge has its own capacity and duration.
How does activated carbon retain substances in water?
By adsorption. Substances collect on the surface of the coal, where the water touches the solid material. US Environmental Protection Agency (EPA) explains why it works: the highly porous structure of charcoal provides a large surface area for contaminants to attach to. The EPA also points out that activated charcoal is often used in drinking water treatment for naturally occurring organic compounds, compounds that impart taste and odor, and synthetic organic chemicals.
However, any cartridge has a limited capacity. The fact that two devices have activated carbon does not mean that they have the same capacity or the same maintenance. Therefore, in the tables below, the data is for the cartridge of each device.
Activated carbon in treatment plants and at the tap
At the Chirița station in Iași, granular activated carbon filters perform the final filtration and correct the taste and odor, according to summary of the 2023 Water Safety Plan. After them, the water enters a tank where chlorine gas is injected.
Then the law intervenes. Government Ordinance No. 7/2023 requires that, in the distribution network, free residual chlorine remain between 0.1 and 0.5 mg/l throughout the entire route, from the connection to the end of the network.
Do you taste or smell it? A ceramic and activated carbon filter, mounted on the tap, retains it right at the point where you use the water. You can find the chlorine values published for your city on our pages for Cluj-Napoca, Bucharest and Iași.
Where to find activated carbon in the Olympus range
You can find activated carbon in Olympus kitchen filters, in the mini faucet filter, in the thermos bottle, in the bathroom filter, and in the reverse osmosis system.
| DEVICE | How activated charcoal is used | Price |
|---|---|---|
| Olympus countertop water filter | Compact activated carbon ceramic filter | 424 LEI |
| Olympus undercounter water filter | Same ceramic cartridge with activated carbon | 627 LEI, with faucet included |
| Olympus GIGA countertop water filter | Same type of cartridge, with higher capacity | 545 LEI |
| Mini faucet filter | Compact activated carbon inside the ceramic filter | 149 LEI |
| 740 ml thermos bottle | PP filter with activated carbon, in straw | 193 lei |
| Bathroom filter | Activated carbon and antimicrobial copper alloy | 249 LEI |
| Reverse osmosis system | Compact activated carbon cartridge and activated carbon post-filter | 1375 LEI |
Prices are taken from the product pages. For countertop and undercounter models with ceramic cartridges, we have switched to the 0.5 micron version. How long each cartridge lasts and how much a replacement costs, see below, in the duration section.
Kitchen filters
In Olympus antimicrobial filters, the basic cartridge is made of ceramic and compact activated carbon. According to the product description, it retains chlorine, pesticides and heavy metals. Mineral salts and trace elements pass further.
Countertop and undercounter filters are manufactured in Greece by Center Plus SA., and it recommends the 0.5 micron version. On the pages of the countertop and undercounter filters it is written that the antimicrobial protection of the device destroys up to 95% of the microbes inside the device within 2 hours. Hesitating between the faucet filter and the filter jug? You can find the comparison in the article filter jug or faucet filter.
The minifilter and the thermos bottle
The Olympus mini filter mounts directly on the faucet and has compact activated carbon inside the ceramic filter. It is designed for low-consumption filtered water, for example for students or those living alone. It does not fit on shower faucets.
The 740 ml thermos bottle has a PP filter with activated carbon in the straw, which improves the taste and smell of the water. The filter holds up to 300 liters. That means about 400 refills. A new one costs 49 LEI and is easy to change. Before first use, leave it in water for 10 minutes, and the water in the bottle should not exceed 60 °C for optimal filtration.
Shower filter and reverse osmosis
The Olympus bathroom filter is mounted between the faucet and the shower hose. Its website states that the antimicrobial copper alloy helps retain chlorine at high temperatures. The replacement cartridge costs 165 LEI.
The reverse osmosis system has two stages of activated carbon. The first is the compact cartridge, which retains chlorine, pesticides, asbestos and heavy metals. The second is the T33 post-filter, which improves the taste of the water before consumption.
How long does an activated carbon filter last?
It depends on the device. The basic Olympus ceramic cartridge with activated carbon holds 8,000 liters of water (14,000 liters for the GIGA) or one year of use, whichever comes first. The other activated carbon cartridges have different capacities and replacement intervals, as listed in the table.
| DEVICE | When to change the cartridge | Replacement cartridge price |
|---|---|---|
| Countertop or undercounter filter | 8,000 L or 1 year of use, whichever comes first | from 249 LEI |
| GIGA filter | 14,000 L or 1 year of use, whichever comes first | from 330 LEI |
| Thermos bottle | up to 300 L | 49 lei |
| Bathroom filter | 1 year or 30,000 L | 165 lei |
| Reverse osmosis, activated carbon cartridges | 9-12 months | 138 lei (CTO), 77 lei (T33) |
To keep track, write down the installation date. The company “ Center Plus ” sends you a notification when the time for replacement is approaching. In kitchen filters, the ceramic cartridge is cleaned every 3-4 months or when the flow rate decreases noticeably, under cold water, without detergents. Cleaning does not postpone the replacement, however.
Activated charcoal and mineral salts
The basic Olympus cartridge, with ceramic and activated carbon, lets mineral salts and trace elements pass through. The cartridges for limescale and nitrates are made of other materials. For them, the double and triple models have resin cartridges. In the reverse osmosis system, the calcium and magnesium salts are retained by the membrane.
The single filter, with ceramic and activated carbon, retains chlorine, pesticides and heavy metals. The double model adds a cartridge for limescale or nitrates. The triple adds both. You can find the countertop and undercounter models, single, double or triple, in the category Olympus antimicrobial water filters.
For the whole house, there is the 3/4″ central filter, which retains sediment and large particles. For chlorine in drinking water, you combine it with an activated carbon kitchen filter, as shown in the guide on the water filter at the entrance to the house.
Frequently asked questions
What does an activated carbon filter retain?
According to the EPA, activated carbon is used in drinking water treatment for naturally occurring organic compounds, compounds that give taste and odor, and synthetic organic substances. It retains them by adsorption on its surface. In Olympus kitchen filters, activated carbon works together with a ceramic filter and retains, among other things, chlorine, pesticides, and heavy metals.
Does the activated carbon filter retain limescale?
The Olympus basic cartridge, no. The ceramic and activated carbon in it let the mineral salts and trace elements pass through. For limescale you need the double model, with limescale cartridge, or the triple one.
How often do I change the activated carbon filter?
The Olympus basic ceramic cartridge with activated carbon needs to be replaced after 8,000 liters of water (14,000 liters for the GIGA) or after one year of use, whichever comes first. In the thermos bottle, the filter holds up to 300 liters.
How much does an Olympus activated carbon water filter cost?
Prices start at 149 LEI, which is how much the mini faucet filter costs. The thermos bottle costs 193 LEI, the bathroom filter 249 LEI, and the countertop filter 424 LEI. The under-counter one costs 627 LEI, with faucet included. For countertop and under-counter, the price is for the 0.5 micron version. Courier shipping costs 33 LEI throughout Romania.
Can I put hot water in the thermos bottle with filter?
Only up to 60 °C. Above that, filtration is no longer optimal. Before first use, hold the filter in water for 10 minutes to activate it.
