Hello Ladies,
I have a sub to Ancestry and did a look up on those records for Grattan Hardy...sorry to say that they are not much help.
Under Canadian Immigration Records - Part 1 there are 3 records.
1882 - Ships List Arrivals at the Port of Halifax
Grattan Hardy - age 20 - arrived on the Circassian
National Archives of Canada Microfilm reel C-4511 Page 8
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1884 - Passenger List Port of Halifax
Grattan Hardy - age 25 - arrived on the Circassian
National Archives of Canada Microfilm Reel C-4512 Page 2
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1883 - Passenger List Port of Halifax
Grattan Hardy - age adult - arrived on the Sarmatian
National Archives of Canada Microfil Reel C-4512 Page 8
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Under Passenger an Immigration Lists - 1500s to 1900s - there is 1 record and it is a repeat of the 1884 record but quoting a different source.
Source: SHEARON, JIM. "'Home Children' Research Continues. 'Home Children' Passenger List for the Year 1884." In Anglo Celtic Roots (British Family History Society of Greater Ottawa), vol. 3:4 (Fall 1997), pp. 12, 22-26.
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So it looks as though he may have travelled back and forth to Canada - maybe on business or visiting a relative.....I can find no other record of him - so I don't think he stayed in Canada...if you look at those microfilms, you may be able to find out what he was doing.
Sorry I couldn't help more

Alice