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Clarisink RO-500 tankless reverse osmosis systemIn stock · ships free
Reverse Osmosis

Clarisink RO-500 Tankless Reverse Osmosis System

£249.00

VAT included · Free UK delivery · Typically arrives in 4–21 business days

  • Shipped via UK Tracked Delivery
  • 60-Minute Simple DIY Setup
  • 2-Year Comprehensive Warranty
  • Engineered for Hard UK Tap Water

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  • Free UK delivery on every order, no minimum spend
  • 2-year warranty on all filtration systems
  • 30-day returns if it isn't right for your kitchen
  • Fits a standard UK cold feed — no plumber required
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Best under sink water filter UK families can rely on

Finding the best under sink water filter uk families can rely on is essential if you want to eliminate cloudiness, chemical odours, and heavy limescale from your daily kitchen tap water.

About this product

The RO-500 removes the storage tank. Instead of filtering slowly into a reservoir, a booster pump pushes water through the membrane fast enough to serve the tap directly. You get back the cupboard space the tank would have taken, and you never draw down a half-empty tank.

The pump has a second benefit that matters in parts of the UK: reverse osmosis needs pressure to work, and homes at the end of a long run or on an upper floor often do not have enough of it. A pumped system keeps filtering where a pressure-fed one would slow to a dribble.

The fifth stage adds calcium and magnesium back after filtration. This is a taste decision rather than a health one — RO water is safe without it, but many people find it tastes thin, and remineralisation puts the body back.

The catch is power. This unit needs a 13amp socket under the sink. Check for one before you order.

Dispatched from our UK warehouse, with delivery in 4-21 business days depending on the item. That is slower than a next-day marketplace and we would rather say so up front than surprise you at the door.

Technical specifications

Connection size
Standard UK 15mm push-fit / compression
Micron rating
0.0001 micron
Lifespan
6 months or 4,000 litres (whichever comes first)

Litres and centimetres are used throughout. Cartridge life is measured in litres of filtered water, so heavily used households will change theirs sooner.

Specifications

Filtration stages5 (sediment, carbon, carbon block, RO membrane, remineralisation)
Membrane rating0.0001 micron
Rated output500 GPD (approx. 1,900 litres per day)
Tap flow rateapprox. 1.2 litres per minute
StorageNone — tankless, filters on demand
Waste-water ratioapprox. 1.5:1
Pre-filter life6-12 months
Membrane life2-3 years
Power requiredYes — built-in booster pump, 13amp socket needed
Under-sink footprintapprox. 42cm H x 18cm W x 40cm D
Minimum mains pressure1.0 bar (pump-assisted)

Figures marked with this symbol are provisional and are being confirmed against the manufacturer's datasheet. We publish them as estimates rather than leaving the row blank, and we do not claim any certification or test result we cannot evidence.

What this filter addresses

  • Dissolved solids (TDS)
  • Chlorine and chloramine
  • Fluoride
  • Heavy metals including lead
  • Sediment and particulates

What it will not do

  • Needs a 13amp socket under the sink. If you have no power there, you need the RO-400 instead — this is the single most common reason a tankless unit has to go back.
  • The booster pump is audible while filtering. It is not loud, but it is not silent either.
  • Still wastes water to the drain, though less than a tanked system.
  • Filters one tap only, not the whole house.
  • The remineralisation stage restores taste but does not turn RO water into mineral water.

Will this fit?

Check these before you order — they are the questions we are asked most often.

  • Requires a 35mm sink or worktop hole for the included designer tap
  • Requires a 13amp power socket under the sink
  • Needs a waste-pipe connection for the drain line
  • Takes replacement cartridge AF-RO400M (membrane) and AF-CBC1 (carbon block)

Still not sure? Send us your sink and pipework details and we will confirm before you buy.

Not sure which RO system?

The RO-300, RO-400 and RO-500 differ on output, footprint, waste water and whether they need a power socket. Compare all three side by side before you commit.

Compare RO-300 vs RO-400 vs RO-500

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