I just watched James Hoffman compare some different minerals, and Perfect Coffee Water (PCW) was the best tasting for the medium roast he used. It got me thinking about trying it in my espresso machine since most of what I drink is city+ to full city. I currently use Third Wave Water's espresso profile.

PCW claims their minerals are safe for espresso machines. The ingredients are Sodium bi-carbonate, calcium chloride, and magnesium chlorides.

I don't know the concentration of chloride, but La Marzocco USA recommends using water that has less than 30 mg/L of chloride to prevent pitting, while Synesso recommends no more than 5-15 mg/L depending on pH and alkalinity. Do you think would there be potential for limescale buildup with the calcium and bicarbonate? For comparison, Third Wave's espresso profile ingredients do not contain any chlorides or calcium.

PCW claims that most espresso machine manufacturers they have spoken with and/or use their water on their demo bars etc. talk about the grains of hardness, not necessarily individual ingredients. This is because what matters is that the mineral solution in the water is balanced and has the least likely chance of falling out of the solution and causing scale.

Basically, they claim grains of hardness and balance are key and what makes Perfect Coffee Water safe to use in espresso machines.

Would you take the risk to put it in your machine?

I think I might at least try some PCW with my Hario Switch once I run out of the Third Wave's classic profile to at least see if it tastes any better. It might be a while though since I mainly drink espresso... maybe I should try making some iced coffee this summer.

Trinity300 wrote:PCW claims their minerals are safe for espresso machines. The ingredients are Sodium bi-carbonate, calcium chloride, and magnesium chlorides.

I don't know the concentration of chloride, but La Marzocco USA recommends using water that has less than 30 mg/L of chloride to prevent pitting, while Synesso recommends no more than 5-15 mg/L depending on pH and alkalinity. Do you think would there be potential for limescale buildup with the calcium and bicarbonate? For comparison, Third Wave's espresso profile ingredients do not contain any chlorides or calcium.

The perfectcoffeewater.com web site says nothing whatsoever about what minerals they are using, but if it's true that calcium chloride and magnesium chloride are their hardness minerals then you can expect significant chloride. Even if they are making a low hardness water, at 3 gpg (51 mg/L CaCO3 equivalent) out of CaCl2 and MgCl2, you can calculate that you would have 36 mg/L of chloride ion -- above typical recommendations. And most likely their water has more hardness and therefore higher chloride than that. With respect to scale risk, you'd need to know the calcium and bicarbonate numbers to guess about that, and they (PCW) choose to not tell us.

With respect to TWW, they are more forthcoming about their ingredients on their web site, and have shared actual numbers with us here on HB. Their espresso formula contains no chloride, although it does have a little calcium in the form of calcium citrate, and quite a lot of magnesium sulfate.

Trinity300 wrote:PCW claims that most espresso machine manufacturers they have spoken with and/or use their water on their demo bars etc. talk about the grains of hardness, not necessarily individual ingredients.

Many machine manufacturers do keep it simple and just advise that the water have low hardness, some of them recommending that total hardness be less than 3 grains per gallon if using unsoftened tap water. That helps keep the machine unlikely to have problems with calcium carbonate or calcium sulfate deposits. But it's really just a convenient oversimplification and misses the importance of things like alkalinity and chloride for espresso machine health.

Trinity300 wrote:Would you take the risk to put it in your machine?

I would not.

homeburrero wrote:The perfectcoffeewater.com web site says nothing whatsoever about what minerals they are using, but if it's true that calcium chloride and magnesium chloride are their hardness minerals then you can expect significant chloride.

They sent it to me in an email. I wish they labeled their products and/or put it on their website.

homeburrero wrote: With respect to TWW, they are more forthcoming about their ingredients on their web site, and have shared actual numbers with us here on HB. Their espresso formula contains no chloride, although it does have a little calcium in the form of calcium citrate, and quite a lot of magnesium sulfate.

I don't know why I said TWW does not include calcium... probably was just late when I posted.

Also, thanks for your opinion on not using PCW in an espresso machine. I guess TWW espresso profile is a bit safer to use in an espresso machine because of the lack of chlorides.

I highly recommend you get a TDS tester. You can get the Third Wave TDS reader for $15. You can't tell a whole lot of what's in the water, but at least you know theres something there. It gives you a good baseline. Almost like doing a compression test on a car. At least you can see if its a minor issue, or a major one. Test the water you use before putting the compounds in. Test after also.

I'm still very new here so I'm just learning, is RO water not the best for coffee? I have heard a long time ago that the minerals wee important in coffee but the mind plays tricks on you because all bottled water is RO and it's recommended to keep from scale and deposits in the machine. I have 0 TDS water ( inline TDS meter on my RODI for my home specifically the saltwater aquarium, but used in other parts of the house for drinking water baby formula and all that course this is Teed off before the DI resin. should I be using something else for my coffee?

Again I'm very new and just learning this craft/hobby so i appreciate your patients.

I used pretty good RO water and TWW for three years. If you look up a previous thread of mine youll see i had scale on my mushroom in 3 years and my steam gauge tube got plugged with some crud. I had a brass plated mushroom and they are susceptible to scale. A stainless mushroom fairs far better. If i were doing it again id try RO and potassium Bicarb. See the water forum. Also not all RO supplies are great. Especially some supermarkets as they dont maintain them well. My RO measures 5 on my TDS meter. Ive got a bunch of TWW and i now use 1/2 as much as they recommend.

Mhart032 wrote:I have 0 TDS water ( inline TDS meter on my RODI for my home specifically the saltwater aquarium, but used in other parts of the house for drinking water baby formula and all that course this is Teed off before the DI resin. should I be using something else for my coffee?

There are two reasons for not using that in an espresso machine. The first is that many machines rely on water sensors that require at least a small amount of conductive ions in the water. The other is that water this pure will be slightly acidic due to the carbonic acid that comes from dissolved atmospheric CO2, and that invites corrosion of coffee machine components.

You can fix both these issues with the addition of a small amount of bicarbonate. It raises the pH and alkalinity (acid buffering capacity). The most popular water recipe on this site is the R Pavlis recipe, which simply adds about 100 milligrams (0.1 gram) of potassium bicarbonate per liter of water. You can use plain old sodium bicarbonate (baking soda) from your kitchen cabinet -- it's lighter so you'd need about 84 mg per liter to get the same buffering effect.

Thank you, that's great information, as I was prepared to run the RO line to the machine for easy access to the water source. The fridge water has a TDS of roughly 10PPM TDS is this still too low?

Sorry guys i didn't mean to hijack the thread.

Mhart032 wrote:The fridge water has a TDS of roughly 10PPM TDS is this still too low?

I think that's low enough that some water sensors might have trouble, also low enough to worry about corrosion and worth spiking up with addition of a little bicarbonate.