There was a disagreement in our shul as to when to put back the Poroches (curtain in front of the Aron Hakodesh) that is removed during Tisha Beav. Is it after Chatzos (midday) or at the time one begins Maariv. What is correct.

There are different traditions. Some maintain that it is replaced after Chatzos or for Mincha. (Mishulchan Avoseinu p. 273, Nessivos Hamarav – Morocan Traditions p. 213 and others). Others replace it for Maariv at the end of the Taanis, as is the minhag of the Toronto Kolel and many other congregations.