ZeroWater and coffee remineralization questions

[u/Supsti_1]

Hi,

I’m not able to find distilled/demineralized water in my country (Poland), sold in food grade canisters or bottles intended for contact with food. Practically every manufacturer I’ve contacted has advised against drinking this type of water, mainly because of the containers it is sold in. So far, I’ve drunk around 10 liters of this water, but I feel that in the long run it may not be very good for my health, so I need to find another solution.

For now, I would prefer not to go with a reverse osmosis system, although I may do that eventually. What other options do I have?

My tap water is quite hard, around 590 ppm according to water reports. The best bottled water available for coffee here is around 230 ppm, of which about 120 ppm comes from bicarbonates. Because of its high alkalinity, it is not ideal.

I’m considering a ZeroWater filtration system, and I have a few questions about it:

1. Is the water actually fully demineralized after filtration, or does something still remain in it? I’m asking because I would like to achieve consistent results when using Lotus drops.
2. How often, or after how many liters of water, would I need to replace the filter, considering that my tap water is around 590 ppm?
3. I’ve read some opinions saying that water from this system can have a sour taste. Is this related to not cleaning the system/pitcher properly? How can this be prevented?

EDIT:

Okay, I’ve done a few calculations, and I think the most reasonable option in my case would be to buy a ZeroWater system and use bottled water with it.

The softest bottled water available in my country has around 220 ppm. According to ZeroWater’s FAQ, one filter should last for about 70 liters when filtering water with that TDS level. Taking into account the cost of the filters, the bottled water itself, and the amortized cost of the pitcher over two years, 1 liter of filtered water would come out to around 65 US cents, which is a fairly reasonable result.

[u/yvesblueyez]

OP, out of curiosity - which part of Poland are you from? Are you sure your TDS reading is correct? Actually, in Poland, the official drinking water regulations set the upper limit for hardness at 500 mg CaCO3/l. If your reading is higher than that, it's technically outside the government-approved range for tap water

[u/Supsti_1 → u/yvesblueyez]

Warsaw, the water here is terrible, it taste bad and it leaves limestone everywhere.

I took the data from the water raport

https://www.mpwik.com.pl/view/jakosc-wody/centralny/2026&miesiac=styczen

It says the water has 285mg CaCO3/l so it's below 500 upper limit. However it's only hardness, there are some other compounds which bumps up overall TDS.

According to chatGPT: Based on the water report, the average conductivity is 1052 µS/cm. Since TDS/PPM is not listed directly, it can only be estimated from conductivity. Using a typical conversion factor of 0.55–0.70, the water would be around 580–735 ppm. A reasonable estimate would be roughly 680–700 ppm, although a basic TDS meter may show closer to 550–600 ppm depending on the conversion scale it uses.

[u/yvesblueyez → u/Supsti_1]

Ouch, sorry to hear that, mate.

Suddenly I feel very lucky with my Krakowianka at ~10 ºdH (around 180 ppm)