Water tastes metallic, bitter, or has a strong off-flavor.

Safety first: Taste issues are usually low risk but always discard suspect water or coffee.

• Change water: Empty and rinse the tank. Refill with fresh, filtered water of appropriate hardness (not distilled).
• Remove softener: If using a Lelit in-tank softener cartridge, remove it temporarily and test taste. Replace the water softener filter if it is old or slimy.
• Flush thoroughly: Run several full tanks of water through the brew and steam circuits to flush residues.
• Descale and clean: Perform a full descaling and backflushing with espresso cleaner to remove scale and coffee oils.