LET´S TALK ABOUT V60
We roast/profile our coffees for medium hardness water, around 120ppm, as the water sits in the 100-160 range in the Czech Republic. We recommend a Brita filtration kettle or a similar one, if you have access to it at home. If you work in a cafe, you're using filter water anyway.
Water too soft extracts more acidity and the brews lack a bit of sweetness and body. Water too hard dulls the brew, it tends to be heavy, less profound and more bitter. Filtered water or bottled water with something of a closer ratio of Ca:Mg being 1:4 makes the brews juicy, sweet and balanced to us.
About the recipe, V60:
Around 1:15 ratio . We use off-boil water as it properly extracts the flavors and you get more body from the coffee, in our experience. Bloom should be around 1:3, meaning 60g of water at least. Gently agitate the coffee with a spoon. NSEW, make it all wet. Total brew time in 2:05-2:25. Swirl after the final pour, tap with the brewer. That levels the coffee bed and reduces channeling.