Perlow was born in Koidanov (present-day
Dzyarzhynsk, Belarus) to Rabbi Baruch Mordechai Perlow (1818–1870), the second Koidanover Rebbe. He was the great-great-grandson of both Rabbi
Mordechai of Lyakhavichy (Lechovitch) (c. 1742–1810) and Rabbi Asher Perlow of Karlin. He became the third Koidanover Rebbe upon the death of his father in 1870. The new rebbe's charismatic personality and scholarship attracted thousands of Hasidim to Koidanov. In his writings and demeanor, Rebbe Aharon embodied the "mystical-charismatic style" of the Rebbes of
Karlin-Stolin, of which Koidanov is a branch. He also authored a
siddur entitled
Seder Tefilot Yisrael Or Hayashar ("The Direct Light: Order of Prayers of Israel"), in which he enumerated "eight mystical practices for spiritual perfection". This siddur is still used by Koidanover Hasidim today. ==References==