Add 2-3 Tbsp citric acid to water reservoir.
Mix
Pull from both the brew head and steam wand until you have pulled 1/4 tank into machine
Turn off (best to operate cold)
Let sit for 20 minutes
flush remaining water
flush again with clean water

Back-flushing

Adding a Water Intake

A float valve was added in order to never have to add water manually to the espresso machine.

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