Some have a minhag to eat Matza on Pesach Sheini it is brought down in the siddur of the Yaavetz (Rav Yaakov Emden) that it was revealed to him from the heavens that the kedusha of pesach and matzah lasts until pesach sheni because when they went out from Egypt they ate the matzos that they came out with until the 15 of iyar.
Some dont say tachnun.
Nitai Gavriel (Pesach Vol 3 Chapter 57) brings several Pesach Sheni customs. Among them:
To increase in Simcha (source: the Chida)
To read the parsha of Pesach Sheni and learn its Halachos (source: The Shalo).
To read the Parsha of the Nesi'im (source: The Shalo).
To visit the grave of Rabbi Meir Baal HaNeis in Teveria
(this is a sefardi custom sourced from many places). Some object to the festive nature of this practice.
To visit the grave of Rabbi Yehuda Bar Illoi (a custom of residents of Tzefas).
He also mentions in a footnote that one of the objections Misnagdim had to the practices of Chassidim was making a meal on Pesach Sheni even if it was one of the days of בה"ב.
Some dont say tachnun.
Nitai Gavriel (Pesach Vol 3 Chapter 57) brings several Pesach Sheni customs. Among them:
To increase in Simcha (source: the Chida)
To read the parsha of Pesach Sheni and learn its Halachos (source: The Shalo).
To read the Parsha of the Nesi'im (source: The Shalo).
To visit the grave of Rabbi Meir Baal HaNeis in Teveria
(this is a sefardi custom sourced from many places). Some object to the festive nature of this practice.
To visit the grave of Rabbi Yehuda Bar Illoi (a custom of residents of Tzefas).
He also mentions in a footnote that one of the objections Misnagdim had to the practices of Chassidim was making a meal on Pesach Sheni even if it was one of the days of בה"ב.