Can I Substitute Tonic Water For Soda Water?
While they look similar, tonic water and soda water are not the same thing and have different flavors. Tonic water is bitter due to the addition of quinine, while soda water is purely carbonated water with no added flavors. Therefore, it is not recommended to substitute tonic water for soda water in a recipe that calls for soda water, as the resulting flavor will be significantly different.