Can the protein/hydration machine be configured for hydration only without protein?

Yes. The machine has a large water barrel and multiple powder canisters (for protein, coffee, milk tea, etc.). For electrolyte/hydration water, there are two options:
(1) Powder Mixing – mix instant electrolyte powder with purified water inside the machine;
(2) Direct Input – fill the water barrel with premixed electrolyte water, and the machine acts as a pure water dispenser with no mixing.