I use cafiza chemical and a brush for the group heads as well as the portafilters. Rinza for the steam wand. Very effective

@Luke Gilbert Haha. Not yet

I'd also like to know. Normally, I take 3-4 espresso shots daily

Sorry for the late update. It's a lot of information that mainly focuses on biological aspects and plant adaptations to various conditions. However here's a simplified version, though with some biological terms. I'm open to any corrections and/or additions. High-altitude coffee beans develop greater density due to environmental stressors; particularly temperature swings that disrupt photosynthesis and force physiological adaptations in the plant. During the day, cooler highland temperatures reduce the efficiency of photosynthesis by limiting the activity of key enzymes like RuBisCO, while cold nights bring the process to a near halt, creating a stop-start rhythm that slows sugar production and extends the cherry's maturation period. This prolonged growth phase allows more sugars and organic compounds to accumulate within the bean, increasing its density. Additionally, high-altitude stressors like intense UV radiation and lower oxygen levels trigger protective responses in the plant, including thicker cell walls and higher concentrations of chlorogenic acids, which further harden the bean's structure. The combination of slower growth, sugar redistribution, and cellular adaptations results in a denser, more compact bean capable of producing the complex acidity and concentrated flavors such as fruity brightness and deep sweetness—l that distinguish high-elevation specialty coffees. The biological processes and plant responses to the harsh conditions are what I found more intriguing; and their part in making the coffee more complex.

Kenyan, Ethiopian and India are some of the best coffees I've tasted. Depending on whether it's esspreso roast or filter roast

@Robert Hamilton Oh really. I'll try that, thank you

@Luke Gilbert OK. Thank you for that feedback