884. Prayer on a Personal Fast Day
127:8 If a person is fasting and he publicizes this fact to make himself look good, he will be punished for it. However, if people try to get him to eat, he may tell them that he is fasting.
127:9 If a person is fasting even a private fast, whether it is a voluntary fast or a fast for a bad dream, he should say "Aneinu" ("answer us") at mincha in the bracha of "Shema Koleinu," the same as one would do on a public fast. Even though he is an individual, he recites the prayer using the plural ("us" rather than "me") so as not to change the wording that was established by the Sages. Before "Yihiyu l'ratzon," he should say "Ribon ha'olamim." (See OC 565:4 for the text of this prayer.)