Water flow is very slow in filtered mode
Slow flow in filtered mode is the most common question we receive — and it almost always has a simple explanation.
- Cartridge not yet activated. After every installation or cartridge replacement, the filter needs 5 minutes of cold water to fully prime. Skipping this step is the most frequent cause of slow initial flow.
- Low water pressure. In flats or on upper floors, water pressure is naturally lower. This is amplified slightly in filtered mode, since water passes through a dense 0.1-micron ceramic.
- Saturated cartridge. If the filter has been in use for a while, slower flow indicates the cartridge is ready to be replaced — a sign it's been working well.
For reference, a healthy filtered flow rate is 5 to 11 litres per minute, depending on your home's water pressure. Filtered mode is optimised for quality, not maximum speed — use unfiltered mode (lever vertical) for washing dishes or filling large pots.
Water flow varies from day to day
Variation in flow from one day to the next is almost always down to your building's mains water pressure — not your filter.
Pressure fluctuates naturally based on time of day, local usage peaks (morning and evening tend to be busier), and occasional maintenance on the distribution network. Your filter simply adapts to whatever pressure is available at the tap.
A quick way to confirm: check whether your other faucets behave the same way. If yes, it's a building or network pressure issue — your Puure is working normally.
The water flow is lower than when I first installed it
A gradual reduction in flow over time is completely normal — and it's actually a sign your filter is doing its job.
In filtered mode, water passes through a 0.1-micron ceramic membrane and a high-density activated carbon block. As the cartridge captures contaminants, sediment and particles over time, the flow naturally slows. This is how all fine filtration systems work.
When the reduction becomes noticeable enough to be inconvenient, it's usually a signal that the cartridge is ready to be replaced.
Use unfiltered mode (lever vertical) for tasks that don't need filtered water — washing vegetables, filling a kettle or pot, or washing up. This extends your cartridge life and gives you full flow whenever you need it.
I see black particles or dust in the water
No cause for concern — this is activated carbon purging from a new cartridge, and it is completely harmless.
Activated carbon is used in water filtration precisely because it is food-grade and safe. The fine black particles you see are simply loose carbon dust that hasn't yet settled within the cartridge. They disappear entirely within the first few minutes of use.
To avoid seeing them at all: always run cold water in filtered mode for at least 5 minutes after installing a new cartridge, before drinking. This flushes and primes the cartridge completely.
This behaviour is the same across all activated carbon filters — Puure or otherwise. If you see it again on a future cartridge replacement, it simply means you started drinking a little before the priming cycle finished.