Plum has the effect of promoting fluid production and quenching thirst. Of course, citron tea's own health value is higher:

Pomelo itself is rich in nutrition, containing far more calcium and vitamins than other fruits. Its vitamin C content is three times that of lemon and orange, and its calcium content is 10 times that of apple, pear and banana. In addition, grapefruit is also rich in natural citric acid and a variety of inorganic salts, which not only contributes to the functions of liver, stomach and lung, but also has the effects of clearing heat, relieving cough and resolving phlegm.