Part 01 · What your machine needs
Chloride and espresso machines: the limits makers set
Most makers that give a chloride number put it at 30 ppm or less. Every figure we've saved, in the makers' own words.
The short answer
Most makers that give a chloride number set it at 30 ppm or less: La Marzocco, Slayer, Lelit and Ascaso among them. Decent Espresso and Meticulous ask for under 10 ppm. These are machine makers' figures, not an SCA standard.
Why makers care about chloride
Chloride is a salt that occurs naturally in water. Makers that set a limit give the same reason: corrosion of metal parts inside the machine.
From the maker
La MarzoccoLa Marzocco machines (Technical Center Water Calculator; names no model)
“Chloride higher than 30ppm: Effects on espresso: increase the perception of sourness and enhance phenolic compounds and astringency. Effects on equipment: chlorides cause severe phenomenon of pitting corrosion.”
From the maker
MeticulousMeticulous Espresso
“Chloride is the enemy of stainless steel. Even at modest levels, chloride ions drive corrosion inside espresso machines. Keep it under 10 ppm, and never remineralize with calcium or magnesium chloride. Use sulfate and bicarbonate based mineral products instead.”
Every chloride figure we've saved
Most makers that give a number put it at 30 ppm or 30 mg/l. For chloride, the two units mean the same amount. Decent Espresso and Meticulous ask for under 10 ppm. Synesso gives a range for the ES.1.
| Maker | The maker's words | Source |
|---|---|---|
| AscasoAscaso Baby T Plus (mains connection) | Cloruro 0-30 ppm | Source for Ascaso, Ascaso Baby T Plus (mains connection) (opens in a new tab)Saved October 28, 2026 |
| AscasoAscaso Baby T Plus (mains connection) | Chlorid 0-30 ppm | Source for Ascaso, Ascaso Baby T Plus (mains connection) (opens in a new tab)Saved October 28, 2026 |
| AscasoAscaso Baby T Plus (mains connection) | Chloride 0-30 ppm | Source for Ascaso, Ascaso Baby T Plus (mains connection) (opens in a new tab)Saved October 28, 2026 |
| AscasoAscaso Baby T Plus (mains connection) | Chlorure 0-30 ppm | Source for Ascaso, Ascaso Baby T Plus (mains connection) (opens in a new tab)Saved October 28, 2026 |
| AscasoAscaso home machines sold by Ascaso-USA: Dream PID, Steel DUO PID, Steel DUO PLUS PID, Baby T Plus (linked under WATER SPECIFICATIONS on each resource page) | Chloride ppm 0 30 | Source for Ascaso, Ascaso home machines sold by Ascaso-USA: Dream PID, Steel DUO PID, Steel DUO PLUS PID, Baby T Plus (linked under WATER SPECIFICATIONS on each resource page) (opens in a new tab)Saved October 28, 2026 |
| Decent EspressoDE1 (all models), Bengle | If using treated tap water, be mindful of the chloride content, since chloride greatly increases the corrosion risk to the machine. Ideally, keep chloride under 10ppm. | Source for Decent Espresso, DE1 (all models), Bengle (opens in a new tab)Saved October 22, 2026 |
Show all 21
| Maker | The maker's words | Source |
|---|---|---|
| La MarzoccoGS3 | the quantity of chlorides be less than 30mg/l | Source for La Marzocco, GS3 (opens in a new tab)Saved October 28, 2026 |
| La MarzoccoGS3 (manual V1.3, superseded) | the quantity of chlorides be less than 50mg/l | Source for La Marzocco, GS3 (manual V1.3, superseded) (opens in a new tab)Saved October 28, 2026 |
| La MarzoccoLa Marzocco home machines | For optimum machine performance, the water properties should fall within the following parameters: Chloride | ppm | 0 | 30 | Source for La Marzocco, La Marzocco home machines (opens in a new tab)Saved October 22, 2026 |
| La MarzoccoLa Marzocco machines (La Marzocco Deutschland FAQ, German market) | Water selection – manufacturer specifications ... Chloride (part of non-carbonate hardness) < 30 ppm | Source for La Marzocco, La Marzocco machines (La Marzocco Deutschland FAQ, German market) (opens in a new tab)Saved October 28, 2026 |
| La MarzoccoLa Marzocco machines (La Marzocco North America water specification; it names no model) | La Marzocco Water Specification ... Chloride ppm 0 30 | Source for La Marzocco, La Marzocco machines (La Marzocco North America water specification; it names no model) (opens in a new tab)Saved October 28, 2026 |
| La MarzoccoLa Marzocco machines (Technical Center Water Calculator; names no model) | Chloride higher than 30ppm: Effects on espresso: increase the perception of sourness and enhance phenolic compounds and astringency. Effects on equipment: chlorides cause severe phenomenon of pitting corrosion. | Source for La Marzocco, La Marzocco machines (Technical Center Water Calculator; names no model) (opens in a new tab)Saved October 28, 2026 |
| LelitBianca V3 PL162T (incl. PL162T-120) | Below you can see the profile that we suggest for a good and stable extraction: Parameter Range Chlorine (ppm Cl2) 0 pH 6,5 - 7,5 Total Hardness (ppm CaCO3) 0 - 110 Carbonate Hardness (ppm CaCO3) 40 - 75 Chloride (ppm Cl-) < 30 Sulphate (ppm SO4) < 50 | Source for Lelit, Bianca V3 PL162T (incl. PL162T-120) (opens in a new tab)Saved October 28, 2026 |
| LelitElizabeth PL92T (incl. PL92T-120) | Please check the Chloride level of the water in the tank. The level should be lower than 30 ppm. If it is higher, please contact your reseller. | Source for Lelit, Elizabeth PL92T (incl. PL92T-120) (opens in a new tab)Saved October 28, 2026 |
| MeticulousMeticulous Espresso | Chloride is the enemy of stainless steel. Even at modest levels, chloride ions drive corrosion inside espresso machines. Keep it under 10 ppm, and never remineralize with calcium or magnesium chloride. Use sulfate and bicarbonate based mineral products instead. | Source for Meticulous, Meticulous Espresso (opens in a new tab)Saved October 28, 2026 |
| MeticulousMeticulous Espresso | Chloride | as low as possible | under 10 ppm | Source for Meticulous, Meticulous Espresso (opens in a new tab)Saved October 22, 2026 |
| RancilioRancilio home espresso machines (US article; names the Silvia Pro X) | are the water quality guidelines we recommend you follow for both the sake of your machine, and your taste buds... Total Dissolved Solids (TDS): 30-150 ppm (parts per million) Total Hardness: 2-3 gpg (grains per gallon) pH: 6-8 Chloride: 0 ppm Chloramine: 0 ppm Silica: <5 ppm | Source for Rancilio, Rancilio home espresso machines (US article; names the Silvia Pro X) (opens in a new tab)Saved October 28, 2026 |
| Slayer EspressoEspresso Single Group (user manual V7.1) | incoming water should have no more than 30ppm chloride content. | Source for Slayer Espresso, Espresso Single Group (user manual V7.1) (opens in a new tab)Saved October 28, 2026 |
| Slayer EspressoSLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') | Water Treatment Requirements ... Chloride: <30 ppm | Source for Slayer Espresso, SLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') (opens in a new tab)Saved October 28, 2026 |
| Slayer EspressoSLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') | Chlorides also encourage pitting corrosion, which causes damage to the machine. Incoming water should have no more than 30ppm chloride content. | Source for Slayer Espresso, SLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') (opens in a new tab)Saved October 28, 2026 |
| SynessoES.1 | Failure to adhere to the listed water quality standards will void the warranty of this machine. ... Chloride 5 - 15 ppm (any Chlorides can be corrosive and harmful) | Source for Synesso, ES.1 (opens in a new tab)Saved October 28, 2026 |
These are machine makers' figures. The 30 ppm line in particular comes from makers like La Marzocco, Slayer and Lelit, not from the Specialty Coffee Association.
The figure can change by model
La Marzocco's manuals for the Linea Micra and the current Linea Mini ask for under 30 mg/l. The manual for the Linea Mini made from 2015 to 2022 said under 50 mg/l. Use the figure for your own model and its manual. Each machine's page shows which one applies.
Chloride is not chlorine
The words look alike, but they're different things. Chlorine and chloramine are disinfectants cities add to tap water. Makers that mention them set much lower figures:
| Maker | The maker's words | Source |
|---|---|---|
| AscasoAscaso home machines sold by Ascaso-USA: Dream PID, Steel DUO PID, Steel DUO PLUS PID, Baby T Plus (linked under WATER SPECIFICATIONS on each resource page) | Free Chlorine ppm 0.0 0.05 | Source for Ascaso, Ascaso home machines sold by Ascaso-USA: Dream PID, Steel DUO PID, Steel DUO PLUS PID, Baby T Plus (linked under WATER SPECIFICATIONS on each resource page) (opens in a new tab)Saved October 28, 2026 |
| AscasoAscaso home machines sold by Ascaso-USA: Dream PID, Steel DUO PID, Steel DUO PLUS PID, Baby T Plus (linked under WATER SPECIFICATIONS on each resource page) | Total Chlorine ppm 0.0 0.1 | Source for Ascaso, Ascaso home machines sold by Ascaso-USA: Dream PID, Steel DUO PID, Steel DUO PLUS PID, Baby T Plus (linked under WATER SPECIFICATIONS on each resource page) (opens in a new tab)Saved October 28, 2026 |
| La MarzoccoLa Marzocco home machines | For optimum machine performance, the water properties should fall within the following parameters: Free Chlorine | ppm | 0.0 | 0..05 | Source for La Marzocco, La Marzocco home machines (opens in a new tab)Saved October 22, 2026 |
| La MarzoccoLa Marzocco home machines | For optimum machine performance, the water properties should fall within the following parameters: Total Chlorine | ppm | 0.0 | 0.1 | Source for La Marzocco, La Marzocco home machines (opens in a new tab)Saved October 22, 2026 |
| La MarzoccoLa Marzocco machines (La Marzocco North America water specification; it names no model) | La Marzocco Water Specification ... Free Chlorine ppm 0.0 0.05 | Source for La Marzocco, La Marzocco machines (La Marzocco North America water specification; it names no model) (opens in a new tab)Saved October 28, 2026 |
| La MarzoccoLa Marzocco machines (La Marzocco North America water specification; it names no model) | La Marzocco Water Specification ... Total Chlorine ppm 0.0 0.1 | Source for La Marzocco, La Marzocco machines (La Marzocco North America water specification; it names no model) (opens in a new tab)Saved October 28, 2026 |
Show all 14
| Maker | The maker's words | Source |
|---|---|---|
| La MarzoccoLa Marzocco machines (Technical Center Water Calculator; names no model) | (Optimal range suggested by La Marzocco) ... Free Chlorine (Cl 2 ) [ppm] | | 0 | 0.05 | Source for La Marzocco, La Marzocco machines (Technical Center Water Calculator; names no model) (opens in a new tab)Saved October 28, 2026 |
| LelitBianca V3 PL162T (incl. PL162T-120) | Below you can see the profile that we suggest for a good and stable extraction: Parameter Range Chlorine (ppm Cl2) 0 pH 6,5 - 7,5 Total Hardness (ppm CaCO3) 0 - 110 Carbonate Hardness (ppm CaCO3) 40 - 75 Chloride (ppm Cl-) < 30 Sulphate (ppm SO4) < 50 | Source for Lelit, Bianca V3 PL162T (incl. PL162T-120) (opens in a new tab)Saved October 28, 2026 |
| Nuova SimonelliOscar (sold in the US as Oscar II), tank and direct-connection versions | Chlorine level less than 0.50 mg/l; | Source for Nuova Simonelli, Oscar (sold in the US as Oscar II), tank and direct-connection versions (opens in a new tab)Saved October 28, 2026 |
| RancilioRancilio home espresso machines (US article; names the Silvia Pro X) | are the water quality guidelines we recommend you follow for both the sake of your machine, and your taste buds... Total Dissolved Solids (TDS): 30-150 ppm (parts per million) Total Hardness: 2-3 gpg (grains per gallon) pH: 6-8 Chloride: 0 ppm Chloramine: 0 ppm Silica: <5 ppm | Source for Rancilio, Rancilio home espresso machines (US article; names the Silvia Pro X) (opens in a new tab)Saved October 28, 2026 |
| Slayer EspressoSLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') | Water Treatment Requirements ... Chloramine: <.1 ppm | Source for Slayer Espresso, SLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') (opens in a new tab)Saved October 28, 2026 |
| Slayer EspressoSLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') | Water Treatment Requirements ... Chlorine: <.1 ppm | Source for Slayer Espresso, SLAYER espresso machines (support article; names no model; says 'All SLAYER Espresso Machines') (opens in a new tab)Saved October 28, 2026 |
| SynessoES.1 | Failure to adhere to the listed water quality standards will void the warranty of this machine. ... Chlorine 0 ppm | Source for Synesso, ES.1 (opens in a new tab)Saved October 28, 2026 |
| Victoria ArduinoEagle One Prima (user handbook) | WATER SPECIFICATIONS ... Chlorine level less than 0.50 mg/l. | Source for Victoria Arduino, Eagle One Prima (user handbook) (opens in a new tab)Saved October 28, 2026 |
Finding your chloride number
Many city water reports list chloride, often among the "secondary" or "aesthetic" figures. Not all do. Of the city reports we hold, the 2025 reports from Dallas Water Utilities and San Antonio Water System don't list it. How to read your water report shows the figures we found.
A hardness strip or a TDS meter won't read chloride. You need a chloride test, such as a drop-count kit. Our test kits page lists what each kit measures.
If your water is over your maker's chloride limit, the water check shows the ways to change that one measurement that your maker's guidance supports.
Sources
Every quote above is the maker's own wording, saved with its link and date. We link only to the makers' own manuals and pages.
- La Marzocco, Water Calculator (La Marzocco Technical Center, techcenter.lamarzocco.com, page footer (c) 2023; linked as 'Water Calculator' from the La Marzocco IE water page and the LM Deutschland FAQ). maker site (La Marzocco Technical Center) (opens in a new tab), saved October 28, 2026.
- Meticulous, Water for Your Meticulous: Preventing Scale and Getting the Best Taste (Meticulous Home, Inc. Help Center; written by Roy Raanani, July 29, 2026). maker help center (opens in a new tab), saved October 22, 2026.
- Ascaso, Ascaso Baby T user manual 81070130 V13 / 2026 (EN-ES-DE-NE-FR). maker manual (opens in a new tab), saved October 28, 2026.
- Ascaso, Ascaso USA Water Specification (one-page PDF, Ascaso-USA; PDF created 2015-09-16, modified 2020-05-08). US distributor document (Ascaso-USA) (opens in a new tab), saved October 28, 2026.
- Decent Espresso, Water recommendations for the DE1 and Bengle (Decent docs; created 2025/11/24, updated 2026/10/20). decentespresso.com (opens in a new tab), saved October 22, 2026.
- La Marzocco, GS3 manual (PDF 'GS3 Manual', created 2019-11-11; the V2.0 text), hosted on home.lamarzoccousa.com. maker manual (opens in a new tab), saved October 28, 2026.
- La Marzocco, GS3 manual MAN.2.1.01 EN V1.3 (PDF created 2016-09-12), hosted on home.lamarzoccousa.com; superseded by the V2.0 text. maker manual (opens in a new tab), saved October 28, 2026.
- La Marzocco, La Marzocco Water Specifications (web page, La Marzocco Ireland/UK site; no US version found). lamarzocco.com (opens in a new tab), saved October 22, 2026.
- La Marzocco, La Marzocco Deutschland FAQ, 'Which water should I use?' (lamarzocco.com/de/en/faq/, article modified 2026-02-11). maker site (La Marzocco Deutschland) (opens in a new tab), saved October 28, 2026.
- La Marzocco, La Marzocco Water Specification (1-page PDF, La Marzocco North America, Seattle; file created 2015-09-16; linked as 'La Marzocco Water Specification PDF' from La Marzocco Home USA's plumb-in article dated 07/09/2026). maker document (La Marzocco North America) (opens in a new tab), saved October 28, 2026.
- Lelit, Lelit Bianca PL162T V3 Extended Guide 2022 REV00 (models PL162T-EU, -AUS, -120, -100; PDF created 2022-05-06; Lelit document hosted by MaxiCoffee). maker document on retailer site (opens in a new tab), saved October 28, 2026.
- Lelit, Lelit Elizabeth PL92T Extended guide 2021 REV00 (models PL92T, -AUS, -AS, -120; PDF created 2021-09-22; Lelit document hosted by MaxiCoffee). maker document on retailer site (opens in a new tab), saved October 28, 2026.
- Rancilio, Rancilio Group North America, "Home Espresso Water Options" (web article, ranciliogroupna.com). maker US subsidiary site (Rancilio Group North America) (opens in a new tab), saved October 28, 2026.
- Slayer Espresso, Slayer Espresso Single Group User Manual V7.1 (August 2022; PDF created 2022-10-21), Slayer support knowledge base 'User Manuals'. maker manual (opens in a new tab), saved October 28, 2026.
- Slayer Espresso, SLAYER Water Treatment Requirements (Slayer support knowledge base article; created 2017-09-20, modified 2025-07-10). maker support site (opens in a new tab), saved October 28, 2026.
- Synesso, ES.1 Water Quality Standards (1-page PDF 'ES.1 water-quality-standards', created 2023-04-17, synesso.com). maker document (opens in a new tab), saved October 28, 2026.
- Nuova Simonelli, Simonelli Group OSCAR instruction handbook, IT/EN/FR/DE/ES (file OscarII-Manual-All.pdf; PDF created 2022-10-27, 112 pp.; on the US distributor's site, simonelliusa.com). maker manual on US distributor site (opens in a new tab), saved October 28, 2026.
- Victoria Arduino, EAGLE ONE PRIMA user handbook (IT/EN/FR, 100 pages; PDF created 2021-11-09; manufacturer Simonelli Group); maker's manual hosted by a retailer (argo.webstaurantstore.com). maker manual (opens in a new tab), saved October 28, 2026.
Questions
Is the 30 ppm chloride limit an SCA standard?
No. It comes from machine makers such as La Marzocco, Slayer and Lelit, and we attribute it to them.
Is chloride the same as chlorine?
No. Chloride is a salt that occurs naturally in water. Chlorine is a disinfectant cities add. Makers set separate, much lower figures for chlorine.
How do I find out my water's chloride?
Look in your city's yearly water report, often among the secondary or aesthetic figures. If it isn't there, use a chloride test. Hardness strips and TDS meters don't read it.
Mineral & Steam does not certify water as safe, guarantee protection from scale, corrosion or equipment damage, or recommend a machine as an overall purchase. It compares the water information you provide with documented manufacturer water requirements and shows the basis and limits of that comparison.
Keep reading
What's in your waterHow to read your city's water report for espressoYour utility's yearly report usually has the numbers a machine maker cares about. Here is where to look, what some large cities list, and where reports fall short.Changing your waterShould I use a water softener with my espresso machine?Some makers call for one above a set hardness. Others are wary of the sodium kind. Here is where each stands.