Barcelona’s tap water is safe to drink, but it has a persistent problem: it is one of the hardest in Spain, with typical values of between 250 and 350 mg/l of calcium carbonate — well above the 200 mg/l threshold the WHO considers soft water. You notice it in the taste, in the limescale on appliances and in the white residue on glasses and kitchenware. A reverse osmosis system installed under the sink eliminates between 95 and 99% of those salts, producing water with a lower dry residue than most bottled water — without bottles, without plastic and without a cost per litre.
At JAG Alcaide we have been installing domestic reverse osmosis systems in Barcelona for decades. We work with Klinwass Montana 5-stage filtration units, fully installed with VAT included and 0% interest finance available. Before installation, we test your tap water quality in front of you with a conductivity meter so you can see exactly where you are starting from and what the result is after filtration.
What does installing a reverse osmosis system in Barcelona actually solve?
Most clients who call us have one or more of these problems: the water tastes or smells of chlorine, leaves white marks on glasses and the coffee machine, or they simply don’t trust the tap water and have been buying bottled water for years. Reverse osmosis does not improve the water slightly — it transforms it completely. The conductivity meter moves from typical Barcelona values of 600–900 µS/cm to below 20 µS/cm after filtration.
What it also resolves, and what many people don’t factor in, is the cost of bottled water. A family of 3–4 people buying bottled water spends an average of €20–40 per month. The unit pays for itself in under two years, and from that point on the cost per litre is practically zero.
What is reverse osmosis?
Reverse Osmosis is a system that consists on reversing the natural flow of osmosis. In the water purification system, the goal is to dilute the salt solution while separating also pure water from salt and other contaminants.
When the natural flow reverses, the water of the salt solution is forced to pass through the membrane in the opposite direction by applying pressure. Through this process we are able to produce pure water by removing the salt and other contaminants.
The reverse osmosis membrane has a pore size much smaller than the size of a bacterium or a parasite. When working properly it will remove all microorganisms from the water that goes through the pipe, producing sterile water.
Do you want to consume high quality water, even with lower dry residue than the bottled water?
We recommend you to try our reverse osmosis system. We offer ourselves to visit the place where you are interested in getting the water tested. Once we get there we will check, in front of you, the level of quality that the water reaching your place has. We will use different testing systems including a dry residue measurer.
Are you aware of the impurities that can be found in the water you consume daily?
Although the water that reaches our homes is supposed to be purified, everyday it is more contaminated by waste coming from domestic, agricultural and industrial sources. In addition it gets even more contaminated in the water distribution pipes that bring the water to our places, this is why generally, the more closer a house is to the sea the more contaminated the water is.
Do you want to consume high quality water, even with lower dry residue than the bottled water?
We recommend you to try our reverse osmosis system. We offer ourselves to visit the place where you are interested in getting the water tested. Once we get there we will check, in front of you, the level of quality that the water reaching your place has. We will use different testing systems including a dry residue measurer.
| Barcelona tap water | Bottled water | Klinwass Montana RO | |
|---|---|---|---|
| Dry residue (mg/l) | 400–600 | 100–300 | <20 |
| Chlorine removal | No | — | ✓ Yes |
| Bacteria removal | Not guaranteed | Yes | ✓ Yes (>99%) |
| Estimated monthly cost | ~€2 | €20–40 | ~€3 (filters) |
| Plastic waste | None | High | ✓ Zero |
| Total price (unit + installation + VAT) | — | — | €720 |
Our reverse osmosis machine
The equipment we offer has 5 stages and offers the following features:
Set dimensions: 430 x 240 x 440 mm
This reverse osmosis system, all completely installed and IVA included will cost you now only 590€ financed at 0% interest.
*This is actually 49.17€ per month or € 1.62 per day during the first year. A great investment considering that this osmosis system will allow you to consume high quality water at all times, even for cooking or preparing tea and coffee.
For more information do not hesitate to contact us and we will try to solve all your possible questions.
What maintenance does a reverse osmosis system need?
The system has three types of filters with different replacement cycles. The sediment and activated carbon pre-filters are changed every 6–12 months depending on use. The reverse osmosis membrane itself has a service life of 2–3 years. The post-carbon filter is replaced at the same time as the membrane. JAG Alcaide provides a maintenance and filter replacement service for all units we install — the client does not need to keep track of which filter is due: we notify you and carry out the replacement at your home.
Frequently asked questions about reverse osmosis in Barcelona
How much does it cost to install a reverse osmosis system in Barcelona?
The Klinwass Montana 5-stage unit, fully installed with VAT included, costs €720. The price includes the complete unit, installation under the sink, an additional tap on the worktop and the initial water quality test. 0% interest finance is also available. There are no hidden costs or additional installation charges.
Is reverse osmosis water better than bottled water?
In terms of dry residue, yes. Reverse osmosis water has less than 20 mg/l of dissolved salts, compared to the 100–300 mg/l typical of bottled water. Furthermore, as it is produced at the moment of consumption, it has no time to absorb compounds from plastic packaging. For cooking, coffee and tea, the difference in taste is clearly noticeable.
Where is the unit installed?
Under the kitchen sink, in the cabinet below. The unit measures 430 x 240 x 440 mm and the 6-litre tank takes up space similar to a large bottle. It is installed with an additional tap on the worktop and requires no building work on walls or floors. Installation takes approximately one hour.
Does it work in rented flats?
Yes. The installation is completely reversible and does not modify the flat’s original pipework. If you move, the unit can be uninstalled and reinstalled at your new home. The only requirement is that the landlord does not object to a small hole in the worktop for the additional tap, which is the same size as a standard kitchen tap.
When do filters need changing and what does it cost?
Pre-filters are changed every 6–12 months (approximately €30–50 for the set). The reverse osmosis membrane is replaced every 2–3 years (€80–120). Total annual maintenance cost ranges from €40 to €80 depending on use and inlet water quality. JAG Alcaide notifies you when a change is due and carries out the replacement at your home.
Can it be installed in an office or commercial premises?
Yes. The same domestic unit works perfectly for offices of up to 10–15 people. For hospitality, professional kitchens or higher flow requirements, we assess the project and recommend the appropriate unit during the preliminary visit.
Is your issue not just water quality but the general plumbing installation? Visit our plumbing and water installations page in Barcelona → for pipe replacement, leak repairs or full network renewal.