Ok so I read Schulmans insanely long water FAQ. Twice. And now I might be more confused than before I read it!

So here goes. According to that info, it states Descale after 2.5-5 grams of scale build up. My tap water is 120 hardness and 80 alkalinity. According to his chart that means 30mg scale per liter of water thru put.. At my rate of use, At the low end of scale (2.5 grams) I could go 6 months without descaling ( a year at 5 g).

Also I think he is saying that inherently my boiler will reduce the hardness to 100 and alkalinity to 50, which is a good level for espresso.

Should I just use tap water? I can't see what real benefit I'd get from bottled or filtered. Am I miss reading his data?

Depending on the total dissolved solids of your water (and its particular mineral composition, though that is much harder to control), its ability to extract desirable compounds from coffee will be affected.
Additionally, plain tap water often contains chemicals used in treatment plants-- potable, but purported to negatively affect the flavor of brewed coffee.
If your total hardness and TDS are both within acceptable ranges, you should be fine with just a carbon filter (a la Brita or Pur).

Here are the specs of tap...

Hardness - 120 mg/L as CaCO3
Alkalinity - 80 mg/L
TDS - 160 mg/L

Does that mean that the boiler will reduce to 100 Hardness and 50 Alkalinity per Jim's FAQ? OR am I misunderstanding this.

Stereo Heathen wrote:.. you should be fine with just a carbon filter (a la Brita or Pur).

I agree. One benefit in typical water utility tap water is that they remove the chlorine. The Brita and Pur jug filters contain a hydrogen based ion-exchange resin that will reduce your alkalinity, slightly reduce your hardness, and temporarily lower (acidify) the pH. Your water at an alkalinity of 80 mg/l should be fine. If your water has high chloride and/or not much alkalinity then using these filters could be a corrosion concern.

Your tap water hardness is a bit higher than the La Marzocco recommendations for espresso machines, also higher than the SCAA recommendation. The downside of that is scaling, so I don't think exceeding those hardness specs is a big deal if you can periodically do a careful descale. Are you testing your water with a kit? If so you might test the Brita/Pur water, both when the filter is fresh and when it's ready to be replaced, then do your descale frequency estimates.

I think your interpretation of the Jim Schulman water faq looks sensible. You used the table for the 95C boiler, and I think the 125C boiler would be more like it, but I'm not familiar with the CC1 boiler temp. Be aware that your PID temp probably includes an offset and is not actually the boiler temp. Using the 125C chart and unfiltered tap water, you might calculate a need to descale on a 3 - 6 month interval.

RyanJE wrote:Also I think he is saying that inherently my boiler will reduce the hardness to 100 and alkalinity to 50, which is a good level for espresso.

Yes, the water that hits your coffee bed will have already dropped scale, and would be lower in hardness and alkalinity than the water going into your boiler. However I think most specifications of ideal water for espresso are focusing on what's good for the machine as well as what's good for the taste. If it were just about extraction and taste I think there are people who would argue that very high hardness numbers would be fine.

homeburrero wrote:I agree. One benefit in typical water utility tap water is that they remove the chlorine. The Brita and Pur jug filters contain a hydrogen based ion-exchange resin that will reduce your alkalinity, slightly reduce your hardness, and temporarily lower (acidify) the pH. Your water at an alkalinity of 80 mg/l should be fine. If your water has high chloride and/or not much alkalinity then using these filters could be a corrosion concern.

Your tap water hardness is a bit higher than the La Marzocco recommendations for espresso machines, also higher than the SCAA recommendation. The downside of that is scaling, so I don't think exceeding those hardness specs is a big deal if you can periodically do a careful descale. Are you testing your water with a kit? If so you might test the Brita/Pur water, both when the filter is fresh and when it's ready to be replaced, then do your descale frequency estimates.

I think your interpretation of the Jim Schulman water faq looks sensible. You used the table for the 95C boiler, and I think the 125C boiler would be more like it, but I'm not familiar with the CC1 boiler temp. Be aware that your PID temp probably includes an offset and is not actually the boiler temp. Using the 125C chart and unfiltered tap water, you might calculate a need to descale on a 3 - 6 month interval.

Yes, the water that hits your coffee bed will have already dropped scale, and would be lower in hardness and alkalinity than the water going into your boiler. However I think most specifications of ideal water for espresso are focusing on what's good for the machine as well as what's good for the taste. If it were just about extraction and taste I think there are people who would argue that very high hardness numbers would be fine.

Thank you for the insite! I used 95c since my machine doesn't use the boiler for steaming, it has a separate thermoblock. However, that could be a bad assumption that I made regarding boiler temp.

RyanJE wrote: I used 95c since my machine doesn't use the boiler for steaming, it has a separate thermoblock. However, that could be a bad assumption that I made regarding boiler temp.

Good point. Your boiler then probably is closer to 95 than it is to 125.