Largest to smallest is way more logical than smallest to largest. You start general and get more specific as you progress. It is in general a better approach to conveying information and cataloging data. Not just dates.

Neither of those are true. Some steel and leathers may be treated to make them anti-microbial, but they are generally not

€150? Damn, I feel bad for any sucker who buys that.

Cool project! Hard to tell from the photo, are the motor mount flanges in the way of the tube fittings? What are you using this pump for?