In stock · ships freeClarisink Limescale Replacement Cartridge
£29.00
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
Secure encrypted checkout · Visa, Mastercard, Amex
- 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
This cartridge holds food-grade polyphosphate, which works by sequestration: it binds calcium and magnesium so they stay dissolved and travel through your pipework instead of crystallising onto it.
That is a different mechanism from filtration, and it is worth understanding because it explains the one thing that surprises people. Test your water after fitting this and the hardness reading will be exactly what it was before. Nothing has been removed. What has changed is that those minerals no longer stick.
Twelve months is the guide, but the cartridge is consumed by the volume of water passing through it rather than by the calendar. Kettle scale reappearing is the practical signal that it is spent.
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
- Not applicable to this component
- 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 type | Polyphosphate scale inhibitor |
|---|---|
| Capacity | approx. 8,000 litres |
| Service life | approx. 12 months |
| Size | Standard 10-inch |
| Replacement | Twist-in, no tools required |
What this filter addresses
- Scale-forming behaviour of calcium and magnesium (sequestered, not removed)
What it will not do
- This inhibits scale, it does not soften water. Hardness readings are unchanged — the minerals simply stop depositing.
- It removes nothing else: no chlorine, no dissolved solids, no metals. It is a single-purpose cartridge and normally runs alongside a carbon block.
- Polyphosphate depletes by volume. In a very hard-water area or a busy household, expect less than twelve months.
Will this fit?
Check these before you order — they are the questions we are asked most often.
- Fits the Clarisink Limescale Defender
- Fits the Clarisink Hard Water Carbon Block Filter
- Standard 10-inch size also fits most third-party under-sink housings
- Not used in the RO-300, RO-400 or RO-500 — RO membranes handle scale minerals directly
Still not sure? Send us your sink and pipework details and we will confirm before you buy.
Customer reviews
Verified reviews from Clarisink customers in the UK. Every review is read by a person before it appears.
No reviews yet
Clarisink is a new shop. We never buy or fake reviews. When our customers write in, their unedited words appear here.
Bought the Clarisink Limescale Replacement Cartridge? We'd genuinely like to hear how you got on with it.