I'll be upgrading my espresso machine in the near future and want to plumb in as part of that. I want to make sure that I get the right filtration / treatment set up for flavor and taking care of the machine. If it's helpful, I think we use about ~10 l of water for drinks/steaming a month.

Here's the latest report for my water district (most relevant numbers on the last page):
https://www.calwater.com/docs/ccr/2019/bg-bg-2019.pdf

It's a combination of two sources, so I made a quick blend of the averages for the two sources given the stated mix of 11% surface and 89% SFPUC:


After reading JSILWF and looking at this handy chart, am I right in thinking that I mostly just need a basic carbon filter (and pressure regulator) rather than a softener?

Assuming I have all of that right (or even if I have it totally wrong!), would love to get filter recommendations for our set up. Thanks!

Bear Gulch water is typically not a blend, but a switch between the two. The Hetch Hetchy / SFPUC water is generally good. The surface water is a little high in mineral content.

cameronr wrote:After reading JSILWF and looking at this handy chart, am I right in thinking that I mostly just need a basic carbon filter (and pressure regulator) rather than a softener?

If those blend percentages are reasonable over the long run, I'd say just go with a good carbon + particulates filter. Your calcium hardness is only 38 mg/L so I think you'll see no limescale deposits. If it spikes for a period of high surface water it may deposit a little but will then tend to dissolve during low hardness water. That alkalinity is fine right where it is. You can't really predict pH with a weighted average of a blend, but it doesn't matter. pH here will be fine.

Jeff wrote:Bear Gulch water is typically not a blend, but a switch between the two. The Hetch Hetchy / SFPUC water is generally good. The surface water is a little high in mineral content.

Interesting, didn't know that. I guess it makes a bit more sense that way.

homeburrero wrote:If those blend percentages are reasonable over the long run, I'd say just go with a good carbon + particulates filter. Your calcium hardness is only 38 mg/L so I think you'll see no limescale deposits. If it spikes for a period of high surface water it may deposit a little but will then tend to dissolve during low hardness water. That alkalinity is fine right where it is. You can't really predict pH with a weighted average of a blend, but it doesn't matter. pH here will be fine.

Great, sounds like I'm on the right track.

Thanks!