Mineral cartridge
Stage 7 — puts beneficial minerals back into the water after reverse osmosis.
Cartridge prices are quoted on request — they move with each shipment, and we will not publish a number that is stale within weeks. We confirm it before any commitment, or it sits inside the annual service contract at a fixed price.
What this stage does
The seventh stage, and what separates the seven-stage system from the six. It puts back a measured amount of minerals such as calcium and magnesium after the membrane removed them — the aim is a rounder taste, not hard water again.
How you know it is overdue
- The water tastes flat compared with what you were used to
- Two years since installation or the last change
Why a range and not one number?
Because what uses a cartridge up is the volume of water passing through it and what that water carries — not the calendar. A household of six gets through one faster than a household of two, and a tank collecting more sand shortens it further. We write the reading down at every visit, so by the second or third we know your home's actual rhythm instead of guessing.
Fits these systems
If your system is on this list, this is the right cartridge.
The rest of the set — RO kitchen filter cartridges
- PP sediment 5µEvery 4–6 months
- GAC carbonEvery 4–6 months
- CTO carbon blockEvery 4–6 months
- RO membraneEvery 4–6 months
- Post-carbon polishEvery 4–6 months
- Alkaline cartridgeEvery 24 months