Ah, the wild card. Seltzer is plain, artificially carbonated water with no added minerals. It’s the purest, most boring cousin, but that’s why people love it—it’s a blank canvas for adding your own fruit or syrup.
So if soda water is a dressed-up version, seltzer is the nudist. And tonic water? That’s a total rebel—it has sugar and quinine, which gives it that bitter botanical buzz. Don’t lump tonic in with the others; it’s its own sweet-sour party.