Water Treatment: Softening & Water Filters for Dishwasher and Coffee Machine
Water treatment is often underestimated in the catering industry – yet the water quality determines the lifespan of your equipment and the quality in the glass and cup. Limescale crusts on heating elements, leaves streaks on glasses and distorts the coffee flavour. This guide shows why filters and softening quickly pay off – especially for dishwashers and coffee machines.
Why hard water is a problem
The harder the water (limescale content), the stronger the effects. The decisive factor is the water hardness in °dH – ask your water supplier or test with a test strip.
| Water hardness | Range (°dH) | Recommendation |
|---|---|---|
| soft | up to 8.4 | Filter usually sufficient |
| medium | 8.4 – 14 | Filter/softening recommended |
| hard | over 14 | Softening/osmosis strongly advised |
Effects of untreated hard water: limescale deposits on heating rods (higher energy consumption, costly repairs), limescale spots & streaks on glasses and cutlery as well as a flat, bitter coffee flavour.
The three water treatment methods
- Filter (activated carbon + limescale protection): reduces chlorine, turbidity and protects against limescale – the standard solution for coffee machines and combi steamers
- Softening (ion exchanger): exchanges calcium/magnesium for sodium – effective against limescale in dishwashers and hot water devices
- Reverse osmosis: almost completely desalinated water – highest level for barista quality and sensitive technology
Dishwasher or coffee machine – what needs what?
| Device | Goal | Solution |
|---|---|---|
| Commercial dishwasher | clear glasses, no limescale on the boiler | Softening + rinse aid |
| Coffee/espresso machine | flavour & brew group protection | Filter, possibly osmosis |
| Combi steamer | avoid limescale in the boiler | Filter/softening |
What to look for when buying
- Capacity: how many litres until cartridge change – adapted to your water hardness
- Bypass setting: good residual carbonate level for balanced coffee flavour
- Change interval: exhausted filters no longer protect – plan changes
- Connection: matching machine and water installation
Frequently asked questions
Do I really need a water filter?
From medium water hardness (above 8.4 °dH) yes – the filter costs a fraction of a limescale boiler repair and noticeably improves flavour and appearance.
How often must the filter cartridge be changed?
Depending on capacity and water hardness – usually after a set litre amount. Many systems have a change indicator.
Is reverse osmosis necessary?
Recommended for very hard water or demanding barista quality. For normal operation, usually a good filter or softening is sufficient.
How do I determine my water hardness?
Through the local water supplier or with a test strip. The °dH then determine the filter choice and change interval.
Water filters at Gastro-Nik
- Bartscher Water Filter KV1 – compact for small machines
- Bartscher Water Filter KV-150 – higher capacity
- Bartscher Water Filter System K1600 EW – for medium demand
- Bartscher Water Filter System K3600L – large capacity
Which water treatment suits your water hardness?
We help with filter choice, capacity and connection – for dishwasher, coffee machine and combi steamer.
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Last updated on 2 September 2026.