Within twenty years, the congregation had grown substantially and it was decided to enlarge the synagogue. During these renovations in 1884 -1885, a mikveh (ritual bath) was added.
By the turn of the century the congregation had outgrown the premises, and a new synagogue, known as the Gardens Synagogue, was built next to the Old Synagogue in 1905. The Old Synagogue continued to be used as a supplementary place of worship and a communal meeting hall. In 1958 it was transformed into the original Old Jewish Museum. In 1996 the decision was taken to incorporate the Old Museum into the new South African Jewish Museum, which was formally opened by Nelson Mandela in 2000.