Water chemistry impacts extraction, flavor, and machine lifespan. Better water often improves espresso faster than expensive gear upgrades.
Why water matters
Very soft water can produce flat extraction. Very hard water can mute acidity and cause scale buildup.
Balanced mineral content improves flavor structure and protects equipment.
Practical home targets
A common starting point is moderate hardness with controlled alkalinity and low temporary hardness risk.
Use tested packets or filtration systems designed for espresso rather than guessing from tap quality.
Keep water consistent
Consistency is more important than chasing theoretical perfect chemistry.
When water changes, your dial-in behavior changes too, so keep your source stable per coffee bag.