First Aid: Water & Descaling (Switzerland)

1. Look up the hardness: on trinkwasser.ch, enter your postcode and choose your water supplier. The platform is run by the industry association SVGW; the water suppliers enter the data voluntarily.
2. If your municipality isn't listed there: every water supplier must provide information on drinking water quality at least once a year, including the total hardness in °fH (Art. 5 TBDV). You'll usually find this drinking water information on the website of your municipality or water supplier. In the canton of Zurich, the «Züri Trinkwasser Map» from the Cantonal Laboratory also shows the measured values per distribution zone.
3. Or measure it yourself with a hardness test strip.
4. Putting it in context: in Switzerland, hardness is given in French degrees of hardness (°fH). Water suppliers classify below 15 °fH as soft, 15–25 °fH as medium-hard and above 25 °fH as hard. A finer scale, for example the one used by the canton of Zurich, subdivides hard water further: from 25 °fH fairly hard, from 32 °fH hard, above 42 °fH very hard. To convert: °dH × 1.8 = °fH.
5. Compare with your machine: La Marzocco, for example, requires 7–10 °fH total hardness. If your water is harder, you need a filter or treated water (section 2).
6. If your machine has a hardness setting, enter your value — otherwise the reminder to descale or to change the filter will come too early or too late.

Sources: trinkwasser.ch (SVGW) — water quality by postcode · Canton of Aargau — information sheet on the duty to inform about drinking water (PDF) · Canton of Zurich — drinking water and «Züri Trinkwasser Map» · Canton of Zurich — water hardness and what it means · La Marzocco — Linea Micra Manual (PDF, water table)

Manufacturer videos on YouTube. They only load when you tap them.

1. Place a tank filter such as BRITA AquaGusto in the water tank. According to the BRITA instructions, AquaGusto 100 fits tanks up to 1.5 l and AquaGusto 250 tanks up to 3.5 l. Remove the protective film first and rinse the filter under running water; the machine should be free of limescale when you put the filter in for the first time.
2. Replace it after 6 months at the latest or after 100 or 250 litres respectively. The litre figure applies at 10 °dH carbonate hardness (around 18 °fH); with harder water or heavy use, replace it sooner. An expired filter no longer protects — use the replacement sticker or put the date in your calendar.
3. Our recommendation: change the filter after half of this lifetime, so after about 3 months or 50 litres (AquaGusto 100) or 125 litres (AquaGusto 250). In our experience, you can taste it in the coffee when the filter capacity drops.
4. Use or change the water in the tank after one day at the latest.
5. Target for your machine water, using La Marzocco as an example: 70–100 ppm total hardness (7–10 °fH) against limescale and 90–150 ppm TDS (all dissolved solids together) for extraction. TDS and hardness are not the same thing. Other manufacturers require other values, e.g. Rocket 4–7 °fH, ECM and Profitec no more than 4 °dH (around 7 °fH) — your manual is what counts.
6. After the filter, measure whether you're within the range, as La Marzocco recommends. Too soft isn't good either: La Marzocco advises against strongly softening jug filters, because they can remove too many minerals from the water.

Sources: BRITA — AquaGusto instruction manual (PDF, German on pp. 8–10) · La Marzocco — Water for Home Espresso Machines · La Marzocco — Linea Micra Manual (PDF, water table) · ECM — FAQ · Profitec — Service & FAQ · Rocket: Appartamento TCA instruction manual

Manufacturer videos on YouTube. They only load when you tap them.

Materials: Brita filters · Hardness test strips in Equipment

For everyone who wants to build their brew water deliberately — with reverse-osmosis or demineralised water as a base. According to Apax, very soft water also works, ideally below 30 ppm:

1. Water with no minerals at all is no good for either the coffee or the machine: La Marzocco names balanced minerals as a prerequisite for good taste and warns that water too low in minerals, such as distilled water, can attack parts of the machine.
2. For brew water that you heat separately, e.g. for filter coffee: 3–4 g of Apax concentrate per litre.
3. In the espresso machine, according to Apax, no more than 1 g per litre — more can damage the boiler over time. Here too, Apax recommends adding the drops to the cup after brewing instead. Apax isn't intended for commercial machines.
4. Or straight into the cup after brewing: filter coffee (200 ml) 5–10 drops, espresso (40 ml) 1–2 drops, milk coffee (150 ml) 3–6 drops.
5. Approach it step by step — «start small, taste as you go».
6. For machines, also comply with the manufacturer's water specification (section 2). Level sensors don't like ultra-pure water: according to La Marzocco, distilled water is a common cause of the "tank empty" message on the GS3 and Linea Mini, because the machines detect the water by its minerals.

Sources: Apax Lab — How to use Mineral Concentrates · Apax Lab — FAQ · La Marzocco — Water for Home Espresso Machines

Play & understand: Water-chemistry simulator · Materials: Apax Lab

1. First check what your manufacturer provides for, and use only the product and programme it names. Never vinegar or home remedies: BRITA warns that even mild acids attack and roughen the components — limescale then builds up there even faster.
2. La Marzocco: the manuals for the home machines don't describe any descaling by you. La Marzocco relies on water that meets the specification and on draining the steam boiler every 1–2 months — how to do this on the Linea Micra is explained in the Espresso machine help. According to the Linea Micra maintenance schedule, the technician checks the boilers after four years and descales them if necessary.
3. Victoria Arduino (E1 Prima): here too, no descaling by you is described. The machine needs very soft water (50–60 ppm hardness, i.e. 5–6 °fH). If your water is harder, Victoria Arduino requires a water softener, and it must remain effective.
4. ECM and Profitec: water no harder than 4 °dH (around 7 °fH). The FAQs of both brands state descaling every 3 months with very hard water, otherwise every 6 months. The instruction manuals are stricter: preventive descaling only after consulting the specialist dealer, i.e. us, and on the ECM Synchronika II only by a qualified technician. The Profitec GO 2.0 has its own descaling programme, which may only be run preventively and only with original Profitec descaler. With both brands, a machine that is already scaled up belongs in the workshop.
5. Rocket, Lelit and Bezzera: Rocket advises against descaling yourself and refers you to authorised Rocket service centres. Lelit: never put descaler in the tank, descaling only by authorised technicians. Bezzera: limescale remover, vinegar or citric acid in the water tank void the warranty.
6. If your manual provides for a descaling programme: follow the instructions exactly and afterwards rinse with fresh water for as long as it specifies.
7. Heavily limescaled or the programme aborts? Don't «force it through» with third-party products — off to our workshop.

Sources: BRITA — Descaling a coffee machine properly · La Marzocco — Water for Home Espresso Machines · La Marzocco — Tech Tips (tip 2: draining the steam boiler) · La Marzocco — Linea Micra maintenance schedule (PDF) · Victoria Arduino — E1 Prima Manual (PDF) · ECM — FAQ · ECM — Synchronika II instruction manual (PDF) · Profitec — Service & FAQ · Profitec — GO 2.0 instruction manual (PDF) · Rocket, Lelit and Bezzera: the respective instruction manual

Stop line: Do not pump any descaling solution through the boiler, E61 group or plumbed-in water connection on your own — only with a programme your manual provides for. Never open the boiler or thermoblock.

Materials: Cleaners & manufacturer-compliant descalers

1. Don't panic: according to BRITA, black debris is just activated carbon from coconut shells and harmless. If you prepare the filter as described, hardly any carbon dust forms.
2. Jug filters (e.g. MAXTRA PRO): submerge the cartridge in cold water and swirl it gently so the air bubbles escape. Pour away the first two litres.
3. AquaGusto tank filter: remove the protective film, rinse the filter thoroughly under running water and place it in the tank — ideally the evening before.
4. Keep to the intervals: change the jug cartridge at least every 4 weeks (MAXTRA PRO: after 150 litres at 10–12 °dH), AquaGusto by capacity, after 6 months at the latest.
5. Store filtered water cool, e.g. in the fridge, and protected from sunlight, and use it within a day. If the off-taste remains: file a complaint about the batch — get in touch with us.

Sources: BRITA — FAQ Filters & Cartridges · BRITA — AquaGusto instruction manual (PDF, German on pp. 8–10)

Stop line: Do not open, «regenerate» or use cartridges beyond their capacity.

Typical signs: the water flow weakens, heating up takes longer, the steam drops off, the descaling indicator comes on more and more often — or the espresso goes flatter even though you changed nothing.

1. Check the water hardness and set up prevention (section 2) — otherwise new limescale will build up again straight away.
2. If your manufacturer provides for descaling: section 4.
3. Otherwise: descaling in our workshop, where the machine is taken apart for it. That's also what Urnex and a Profitec service technician recommend; with the right water, according to the Profitec blog, it's only rarely necessary.

Sources: Urnex — Espresso Machine Cleaning (PDF) · Profitec blog — Cleaning and care of your espresso machine

Service & repairs at the Coffee Coaching Club