His English wife Beatrix Colquhoun (nee Hoile), whom he married.on 15 September 1892 was also an impressionist painter and a former National Gallery school student and had studied art in Paris.
A reviewer in The Bulletin in 1932 notes his conservative impressionist style; Unassuming sincerity marks the work of Alexander Colquhoun, whose paintings are on show at the Grosvenor Gallery, Melbourne.
He is a veteran painter, trained in the orthodox schools, who has abandoned the gallery picture ambition and returned to the simple impression, a far more difficult job.
[14] While a member of the Buonarotti Club Colquhoun, then twenty-three, penned satyrical verse urging the Victorian National Gallery to rehang French painter Jules Lefebvre's 1875 nude Chloé, loaned to it by its purchaser Dr Thomas Fitzgerald, during a scandal about it being displayed on a Sunday.
His critical writing and feature articles including contemporary biographies of Melbourne artists appeared regularly in the Age from 1926 until his death.
[10] He was secretary of the Victorian Artists' Society, 1904–14, a foundation member of the Australian Art Association and in 1936 was appointed a trustee of the National Gallery of Victoria.
[23] He died in East Malvern on 14 February 1941, and was cremated, survived by his wife and three of their four children including Archibald, a painter who married the artist Amalie Sara Colquhoun[24] The Bulletin published a brief obituary:"Artist Alexander Colquhoun, who passed over at 75 in Melbourne last week, was born and educated in Glasgow, and came out to Australia as a young man when the Eaglemont school was flourishing and Conder, McCubbin, Streeton and Tom Roberts were starting.