To start off, I am looking at upgrading to a Linea Mini and am trying to really brush up on my water knowledge in order to try keep the machine in tip top shape. The machine is for my home where it will likely pull anywhere from 2 - 6 drinks a day depending on a variety of factors.

I've recently found myself lost down the rabbit hole researching the best water for espresso / espresso machines. I am looking for some advice on how best to prep my tap water to keep my machine in tip top shape (upgrading machines soon and given the investment required I want to make sure I treat her well). I know there is a balancing act to play in managing the TDS, Hardness and pH levels as to keep the machine from a) buildings up scale and b) corroding due to lack of minerals in the water (at the moment I want to start with best water for the machine and move onto espresso flavouring once I have that down pat). I currently have a two stage carbon water filter under tap which does a good job at removing random flavouring (chlorine?) from the city treated water but does nothing in the way of reducing TDS and nothing on reducing hardness (seems that TDS is in the 130-160 ppm range and hardness is somewhere in the 50-120 ppm range (best I can do with those testing color strips) out of the filter tap. I am thinking of mixing with distilled water to bring down both TDS and hardness without removing too many minerals. Any recommendations?

I am going to be moving houses in the next 6 months or so and don't want to invest in a a new under sink or full home system. I live in Toronto, Canada if that's at all helpful (I found the city water guidelines less than helpful).

Thanks in advance for all the help!

Water is a frequent question here. I'm guessing if you use the search option you'll find something more specific to your water source.

Based on a quick look of the 2018 Toronto municipal water report, it looks like your water has a fair bit of Chloride (opposed to Chlorine) which can cause corrosion. This cannot be removed with standard carbon filtration or water softeners; you would require Reverse Osmosis to reduce it.

The best method, especially for a machine with a tank vs a plumbed in machine, would be to start with Distilled or De-Ionized water and add a blend of salts. The easiest is "rpavlis" water which just uses Potassium Bicarbonate. Search here on H-B for the recipe. Another recipe uses Epsom salts and baking soda which can be found on the Barista Hustle site. In either case, you can mix up concentrated solutions which are then added to a gallon of water; it makes measuring the salt amounts easier.

Thanks this is helpful, I just ordered some potassium bicarbonate to try out the Pavlis recipe. Any thoughts on a 50/50 mix of distilled water and tap water? based on the results I see on the https://www.toronto.ca/wp-content/uploa ... 8-AODA.pdf and the recommended values in https://techcenter.lamarzocco.com/jsp/T ... ulator.jsp seems I should be in decent shape?

jpreiser wrote:Based on a quick look of the 2018 Toronto municipal water report, it looks like your water has a fair bit of Chloride (opposed to Chlorine) which can cause corrosion.

Looking at probably the same online report (https://www.toronto.ca/wp-content/uploa ... 8-AODA.pdf) I agree that it has what I'd call borderline high chloride at 28 mg/L (average). Also has enough hardness (128 mg/L CaCO3 equivalent) and alkalinity (90 mg/L CaCO3 equivalent) that it will need softening.

The Linea Mini factory operators manual recommends that chloride be below 50 mg/L, but the LM USA install guide is more cautious, recommends that chloride be below 30 mg/L. One manufacturer (Synesso) recommends that chloride be below 15 mg/L.

Following jpreiser's advice above about using simple scale free water recipes is the sure fire way to keep you safe from scale and corrosion.

If you really want to plumb it in, I think you'd be OK with a conventional softener, which would leave you with borderline chloride but it would also have that 90 mg/L alkalinity to help alleviate the corrosion concern. I would not use a decarbonizing softener (aka WAC, aka hydrogen exchange softener) with this water because it would reduce your alkalinity and acidify the water - not good when you have borderline chloride. Or of course you could play it very safe and go with an RO unit to get rid of that chloride and then use a remineralizing cartridge or blending valve.

I may be wrong with my understanding of how the chemicals work but wouldn't mixing 50/50 with distilled water help reduce the concentrations to workable levels?

Aside, is Pavlis recipe neutral in that it won't produce scale but also won't corrode the components (thinking distilled and potassium carbonate)?

I've been looking but haven't seen any experience with leaving the machine on vs. turning it off, any thoughts on how the water impacts the machine if its left on 24/7?

CanadianCL wrote:I may be wrong with my understanding of how the chemicals work but wouldn't mixing 50/50 with distilled water help reduce the concentrations to workable levels?

Yes, it would. You'd be down to 14 mg/L chloride and about 64:45 hardness:alkalinity. I'd go with maybe 60% distilled to get it a little more into the non-scaling and lower chloride zone. If you had a fancy RO with a blending valve you could do the same with blending.

CanadianCL wrote:Aside, is Pavlis recipe neutral in that it won't produce scale but also won't corrode the components (thinking distilled and potassium carbonate)?

Yes, the advantage to water like rpavlis' 100 mg/L potassium bicarbonate is that you have good alkalinity, zero calcium, magnesium, silica that might lead to hard scale, zero chloride or sulfate that might be corrosive. Easy to make and seems to be fine for tasty espresso extraction.

CanadianCL wrote:any thoughts on how the water impacts the machine if its left on 24/7?

I can't think of any reason you might want different water for a machine that's on 24/7 as opposed to turning it on/off.