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Clarisink RO-400 replacement membrane cartridgeIn stock · ships free
Cartridge

Clarisink RO-400 Replacement Membrane Cartridge

£39.00

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
  • Secure, encrypted card checkout

Water filter cartridges UK households can fit themselves

Sourcing genuine water filter cartridges uk plumbing setups require is the only way to ensure your system continues to strip away chlorine odours and heavy limescale.

About this product

The membrane is the part of a reverse osmosis system that does the filtering that matters, and it is the part that eventually wears out. Signs it is due: filtered water starts tasting more like tap water, the tank takes noticeably longer to fill, or a TDS meter reading creeps up.

Two to three years is the usual interval, but hardness drives it. In a hard-water area at the harder end of the UK range, plan closer to two.

One thing that genuinely extends membrane life is keeping on top of the pre-filters. They exist to catch sediment and chlorine before either reaches the membrane, and chlorine in particular degrades RO membranes. Skipping a pre-filter change to save money reliably costs more at the membrane.

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

Cartridge typeReverse osmosis membrane
Membrane rating0.0001 micron
Service life2-3 years
ReplacementTwist-in, no tools required
FormatInline RO membrane housing

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)
  • Heavy metals including lead
  • Scale-forming minerals
  • Fluoride

What it will not do

  • This is the membrane only. Your pre-filters run on a much shorter 6-12 month cycle and are replaced separately.
  • Membrane life depends heavily on water hardness and how well the pre-filters have been maintained. A neglected pre-filter shortens membrane life considerably.

Will this fit?

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

  • Fits the Clarisink RO-400
  • Also fits the Clarisink RO-300
  • Also fits the Clarisink RO-500
  • Not required for the Limescale Defender or Carbon Block Filter — those are not RO systems

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

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