Currently figuring out and ideal solution for softer water on my upcoming espresso machine. Chicago water supply is one of the hardest in the country around 8 gpg. Renting so not looking for a full system install. Distilled($2 gallon) + Rpavlis water would've been my solution but not looking forward to lugging multiple gallons of water/grocery run without a car.


So here a potential solution for me that should last a long while. Went Zerowater pitcher with the TDS meter and big filter. Test strips to see the before and after water treatment. I would use the filter for a bit but then just tear it apart from the top and dump out the inside filter material. On the bottom of the filter is a fine mesh stopper that holds all the filtering sediment which I'll keep. I'll add in the resin and it'll be the new filtering solution. I have a 30cup PUR water filter next to my sink that I use for drinking and will run that water through this softening solution for espresso machine and then test the water. If it works well then this solution should last me a long while and the resin is easily rechargable with a salt water flush and rinse for multiple reuses. $36 for 12lbs of resin. Thoughts?

Zerowater pitcher - https://www.amazon.com/gp/product/B01JA5H7GK/

Resin - https://www.amazon.com/gp/product/B079P7QCJF/

Test strips - https://www.amazon.com/gp/product/B08537NDR5/

The problem with ZeroWater and really hard water is that it's uneconomical, the filters lasted barely two weeks for me.

How are you going to measure the hardness with the cation resin? I believe with the TDS meter it will still measure high even though it's non-scaling, but with a test kit you'd get a better idea of the hardness.

Yes what the other commenter said its not economical at all and the Zerowater filters are more or less a gimmick to get distilled water. With regular use these filters only last 15 gallons before they are not safe to run through anymore. Cation resin on the other hand should last much longer with recharge ability and I am simply using the Zerowater filter to house the resin and filter the water to soften it!

I think the strips I've listed should suffice yes. I'll see tomorrow when I get them. TDS meter to see how many particulates in the water in the first place which I've been curious and the hardness strips to measure calcium and magnesium ions. Might not get it all the way but I could always run the water through the filter twice! I'll update my findings

yakster wrote:The problem with ZeroWater and really hard water is that it's uneconomical, the filters lasted barely two weeks for me.

I'm guessing this is affected by the water source. I have a Zero, and it lasts quite a long time. You've inspired me to calculate how many gallons I get on average. I don't actually know.

My biggest issue with the Zero is the funny taste even when it's new. Although other people don't seem to pick it up.

They're up-front about it on their website, "If your water is in the Extreme range [400+] please call and we will help you find an economic solution." Unfortunately I've got 500 ppm water here, and ZeroWater starts to taste fishy after two weeks. I'm interested to hear how this experiment works out. Have you tried a 10" cation water softener cartridge? I guess since you rent, that's not in the cards.

I guess part of my issue with the ZeroWater when I was using it is that we were using it for drinking water too and not just for coffee, if it was dedicated to coffee then it would probably last longer.

cloudyw00 wrote:Yes what the other commenter said its not economical at all and the Zerowater filters are more or less a gimmick to get distilled water. With regular use these filters only last 15 gallons before they are not safe to run through anymore.

I would not call them a gimmick - they are mixed bed ion exchange de-ionizers, which remove all ions down to a few ppm and do what they claim to do. Zerowater has a FAQ that is very transparent about what the filter does, how long it lasts, etc. At Chicago water utility TDS in the 170 ppm ballpark, a $15.00 filter should handle 20 - 30 gallons -- ballpark of 60 cents a gallon. I do better than that buying deionized at my grocery refill station, but I still use Zerowater as my backup.

The Chicago city water (see https://www.chicago.gov/content/dam/cit ... _Q1-Q4.pdf ) is not very hard, but if you use it without some sort of softening you would need to occasionally descale. You could get away with mixing 40% charcoal filtered tap with 60% Zerowater and have water in the typically recommended zones for coffee brewing - about 55 ppm total hardness and about 40 ppm alkalinity as CaCO3. The calcium hardness would be down in the 40 ppm ballpark and would not be scale prone. And the chloride ion would be nice and low around 6 ppm.

You could eliminate your scale risk by conventional softening, and in theory you could do that with your DIY approach. I wonder how well it would work and how much of a pain it may be. Be aware that there may be microbial growth issues with using a filter longer than 6 months, and that recharging the resin requires a careful flush to eliminate every bit of the chloride ion in the salt. To verify softening performance those test strips may be inadequate. You could use an inexpensive API fishcare GH kit, especially if you stretch it*, or maybe spend a bit on a Hach 71A kit which is intended to precisely test low hardness levels.


* instead of using a 5 ml sample in the tube supplied with the kit find a small glass vial that holds at least 10 ml, and use a 10 ml sample. Then each drop corresponds to 8.9 mg/L CaCO3 equivalent.

Guess you are right! I didn't do the exact math but with your calculations .60c per gallon isn't terrible value. And the water outputted is the equivalent of distilled until the filter nears EOL. I'll test out the mix of 40/60 Pur filtered water and Zerowater included with the pitcher to see if that is scale free.

I'll have to see it as well when I get the softening material and pitcher and see the workflow with that. Water flow rate ideally should be limited by the hole on the bottom of the filter and it drains slowly while seeping through the resin media and exchanging Ca and Mg. I'll keep the growth in mind and rotate the resin early since I do get quite a bit so it should last me a while. Thanks for that fishcare GH kit recommendation might just get that over the strips. Awesome advice!

Also wanted to see your thoughts on treating this used machine with potential scale buildup. 1 yr old Rancilio Silvia Pro X preinspection
Machine was used since release Jan 2022 and was from Brita filtered water from Louisville KY tap. He swapped over to gallon filtered water which is even more unknown with hardness. Wonder if its worth taking apart and running light descale or use it for the time being.

cloudyw00 wrote:Also wanted to see your thoughts on treating this used machine with potential scale buildup. 1 yr old Rancilio Silvia Pro X preinspection

I see you have Jim Schulman's advice on that thread. Can't do any better than that. (He's been the expert on this stuff for decades - is the author of the famous Insanely Long Water FAQ.)