Made coffee this morning with distilled + Third Wave Water. Jammy tart cherry acidity with light bitterness, clear and balanced, a touch syrupy. Maybe more acidic than I'd really prefer, but pleasant. Each sip drew me back for another.

Made coffee this afternoon with refrigerator filtered tap water. Big muddy bitterness with a weird astringent cherry pie note lingering far too long at the end.

Both brewed by Ole Kristian Bøen's hybrid Hario Switch recipe, nothing changed other than water.

Next step, ordered a BWT pitcher to swap some of the Calcium in my tap water for Magnesium but stay closer to 110ppm hardness vs. the 180-190ppm you get with TWW (and thus back off the resulting acidity just a touch). Hoping it's a good compromise vs. a full custom water recipe.
@nmeans Looking forward to your findings.
@nmeans Give me some good news.
@mmaa Still working on it! From taste, I think the BWT pitcher is leaving too much calcium in the water. I've got a GH/KH test kit on the way to know for sure from a hard data perspective, and I might do a blind tasting as well.
@mmaa Glad I did the test! I was getting a muddy cup from the BWT pitcher not because it leaves too much Calcium, but because it pulls too much hardness out. Nothing left to extract the coffee. The good news is that because the pitcher pulls carbonate hardness/alkalinity (KH) so low, it’s an excellent base for a water recipe instead of needing distilled. I was right about TWW, though - it’s wildly hard, so no wonder it pulls so much acidity. Gonna write up a blog post about all this soon.
@nmeans Interesting. So do you think you’ll stick with the pitcher, and build up from there? Maybe with something like Lotus.
https://lotuscoffeeproducts.com/collections/all
Products

Lotus Coffee Products
@mmaa Here's where I ended up on all this: https://ruby.social/@nmeans/111052740361685694
Nickolas Means (@[email protected])

After a bunch of experimenting, I'm finally to a coffee water situation I'm happy with! 1. Filter with BWT Pitcher with the pink Magnesium mineralization cartridges to soften Austin tap water to 53.7 ppm GH / 17.9 ppm KH. 2. Measure 300ml filtered/softened water into my kettle (1ml = 1g, so easy to do by weight) and add 3ml of an Epsom Salt / Baking Soda solution to bring GH up to 85 ppm and KH to 40.5 ppm, both right in line with SCA specifications. Yields a deliciously bright, balanced cup!

Ruby.social
@nmeans Excellent. Thank you. Exactly what I was hoping for.