[1] After leaving school, Ennis entered the Post Office,[2] meanwhile studying pianoforte under Edward Dannreuther.

[3] He served as choirmaster and organist at Holy Trinity Church (since demolished) in Knightsbridge from 1887 to 1893, and at St Mary's, Brookfield, from 1893 to 1899.

[5] He did a considerable amount of teaching in Sydney, served for a time as acting city organist, and participated in a series of recitals with renowned Australian pianist Elsie Stanley Hall.

She was remembered for her work with the Society for the Prevention of Cruelty to Animals,[9] Ennis composed a magnificat for soloists, chorus, strings and organ; also a song, "Beautiful Maiden",[1] but pressure of other duties in Australia did not allow him the freedom for further composition.

[3] Friends and supporters of Ennis funded the erection of an ornamented headstone[10] on the couple's grave in the West Terrace Cemetery, and a brass plaque in his memory was placed on the northern wall just inside the western entrance to the Elder Conservatorium.