Head-to-Head Comparison

Both systems sit under your sink and give you filtered water through a dedicated tap. That's where the similarity ends. The technology is different, the filtration depth is different, and the problem each one is best at solving is different.

Feature Reverse Osmosis — €399 Carbon Filter — €199
Removes chlorine & taste ✓ Yes ✓ Yes
Removes limescale (calcium/magnesium) ✓ Yes — 99%+ ✗ No
Removes heavy metals (lead, arsenic) ✓ Yes ⚬ Partially
Removes fluoride ✓ Yes ✗ No
Removes bacteria / microorganisms ✓ Yes ✗ No
TDS reduction ✓ Yes — dramatically ✗ No
Water tastes like premium bottled water ✓ Yes ⚬ Much improved
Reduces scale on kettle / coffee machine ✓ Yes ✗ No
Dedicated pure-water tap included ✓ Yes ✓ Yes
Suitable for renters ⚬ Usually (check lease) ✓ Ideal for renters
Annual filter cost €90/year ~€60/year
Installed price €399 €199

Reverse Osmosis — The Full Picture

Reverse Osmosis System

How it works — and why it's different

Reverse osmosis forces water through a semi-permeable membrane with pores so small they stop virtually everything except water molecules. The result is water with almost nothing left in it — no limescale, no chlorine, no fluoride, no heavy metals, no bacteria. The TDS (total dissolved solids) of Tenerife tap water typically drops from 500–600mg/L to under 20mg/L.

  • Removes 99.9% of dissolved contaminants
  • Dramatically reduces limescale in drinking water
  • Pressurised storage tank — water on demand
  • Dedicated tap fitted to your sink
  • Tastes better than most premium bottled water
  • Less scale on kettle, coffee machine, glass
  • Saves €300–€480/year vs buying bottles
  • Annual filter service: €90
€399 installed
one-time, no subscription
The limescale point matters most in Tenerife

With Tenerife water hardness at 500–600mg/L, a carbon filter won't touch the calcium and magnesium that causes scale build-up and the mineral taste. Only reverse osmosis removes dissolved minerals at that level. If your main concern is water quality — not just taste — the RO is the right tool.

Dedicated reverse osmosis drinking water tap fitted to kitchen sink in Tenerife
The dedicated RO tap sits alongside your main tap. One turn and you have pure, filtered water — no bottles, no fuss.

Under-Sink Carbon Filter — The Full Picture

Under-Sink Carbon Filter

Simpler technology, real improvements

Activated carbon works by adsorption — contaminants stick to the surface of the carbon as water passes through. It's very effective at removing chlorine, chloramines, some organic compounds and anything that causes bad taste or odour. It makes Tenerife tap water significantly more pleasant to drink. What it cannot do is remove dissolved minerals, fluoride, or bacteria.

  • Removes chlorine and chloramines
  • Removes bad taste and odour
  • Removes some organic compounds and pesticides
  • Simple, compact installation
  • Dedicated tap fitted to your sink
  • Ideal for rentals — no permanent changes
  • Annual filter cost: ~€60
  • Does not remove limescale or dissolved minerals
€199 installed
one-time, no subscription
Perfect entry point — genuinely useful

The carbon filter is not a budget compromise. It makes a real, immediate difference to how Tenerife water tastes and smells — especially if you're currently drinking straight from the tap or buying supermarket bottles for taste reasons. At €199 installed it's accessible, simple, and effective for what it does.

Under-sink water filter installation Tenerife kitchen — professional fitting
Both systems sit neatly under the sink. The RO is a little larger due to the storage tank, but both fit in standard kitchen units.

Which One Is Right for You?

Rather than a generic recommendation, here are the four scenarios we see most often — and what we'd suggest in each case:

Scenario 1

Homeowner who wants the best drinking water possible and is fed up buying bottles

The RO system is exactly what you need. It'll pay for itself in under a year if you're currently buying water, and the quality difference is immediate and significant. This is our most popular product for a reason.

→ Reverse Osmosis — €399
Scenario 2

Renter in an apartment who just wants the tap water to taste better

The carbon filter at €199 is made for you. Easy installation, no permanent changes, and you'll notice a real improvement in taste and smell immediately. The best starting point.

→ Carbon Filter — €199
Scenario 3

Family with young children or someone with health sensitivities

When children are drinking tap water daily, the level of filtration matters more. The RO system removes limescale, fluoride, and trace contaminants that a carbon filter won't touch. Worth the extra investment for peace of mind.

→ Reverse Osmosis — €399
Scenario 4 — Best of Both

Homeowner who also wants appliance protection, softer skin and better laundry

The under-sink systems (RO or carbon) only filter your drinking water tap. For protection across your whole home — washing machine, shower, dishwasher — you want a whole house system alongside your drinking water filter. Many of our customers have both. We can quote a combined installation if that's of interest.

→ RO + Whole House System

Your Questions Answered

Will a carbon filter stop my kettle from getting limescale?
No. Limescale is caused by dissolved calcium and magnesium in the water, and carbon filtration does not remove dissolved minerals. Only reverse osmosis removes these at the level needed to prevent limescale. If scale on your kettle or coffee machine is a concern, you need the RO system.
Is RO water actually better than premium bottled water?
In most cases, yes. Reverse osmosis removes more contaminants than most bottled water brands, produces water with a TDS of under 20mg/L (comparable to the best premium brands), and is delivered fresh on demand — it's not sitting in a plastic bottle in a warehouse. The taste is clean and neutral, and many people who were buying premium sparkling or still water are happy switching to RO tap water.
Can I upgrade from a carbon filter to RO later?
Yes, absolutely. Some customers start with the carbon filter at €199 as an entry point and upgrade to the RO later. The installation process for the RO is straightforward regardless of what's already under the sink. The only cost is the difference in system price plus a new fitting for the storage tank.
Does RO water taste flat or empty?
This is a common concern, and occasionally true of very cheap systems. Our RO systems include a remineralisation stage that adds a small amount of beneficial minerals back into the water — giving it a clean, balanced taste rather than the "hollow" flatness some people associate with distilled water. The result is water that tastes clean and fresh, not empty.
What about the waste water from RO? Is it a lot?
RO systems do produce some waste water during the filtration process — the concentrated minerals have to go somewhere. Modern systems are much more efficient than older ones; our systems typically produce 1–2 litres of waste per 1 litre of filtered water, down from the 3:1 or 4:1 ratios of older technology. The waste water goes directly to the drain, so there's nothing to manage on your end.
Not sure? Just ask us.

If you message us on WhatsApp and tell us a little about your home — apartment or villa, renting or owning, main concerns — we'll give you an honest recommendation. No pressure, no upselling. We'd rather you got the right system than the most expensive one.

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Ultra Pure Water Tenerife British-owned water filtration specialists. Based in Tenerife South, serving Costa Adeje, Los Cristianos, Arona and surrounding areas.

Still Not Sure Which One?

Message us on WhatsApp with a quick description of your home and what's bothering you about the water. We'll come back with a straight answer — no sales pitch, no pressure.

Tenerife South based. We typically reply within the hour.

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