"Where is the chili pepper water?"
Translation:Aia i hea ke kai nīoi?
"Wai" is freshwater or is freshwater-based, as in "ka wai hua ai".
"Kai" is saltwater and salt-based things like condiments. That is why it is "ke kai nīoi" - chilli pepper [salt]water. "ke kai" - can also mean gravy, sauce, condiment in general.
Itʻs important to remember that ma ka ʻōlelo hawaiʻi, "wai" does not mean water in general. It is more correct to say "ke kai o ke kai Moana" - the water of the ocean, and not "ka wai o ke kai Moana."
Hope that helps!