From Anambra State, as an amateur, Ekwelum competed in the 1970 Commonwealth Games in Edinburgh, losing in the quarter-final to Irishman John McKinty.
[4] In January 1975 he knocked Eddie Neilson down four times before winning by a send-round stoppage, and a month later lost a narrow points decision to Billy Aird, both of these fights taking place in England.
In December 1976 he beat future world title challenger Lucien Rodriguez on points,[8] then had a run of three defeats; First, in January 1977 he was stopped in the seventh round in Johannesburg by Kallie Knoetze,[9][10] which saw him receive a lifetime ban from the Nigerian Boxing Board of Control for fighting in South Africa.
He returned to winning ways in November 1978 with a fifth-round stoppage of German (BDB) champion Bernd August, and then in 1979 became based back in is home country, the ban evidently lifted.
In November 1984 he lost to Malian Mary Konate, and in his final fight in August 1986, at the age of 38, he was beaten on points by Charles Udalor in a Nigerian heavyweight title clash.