My Great Grandfather arrived in Australia in December 1868 on Boy-Bendixen. The ship sailed again in January 1869, without my ggrandfather. He married in 1872 in Melbourne. I have yet to find what my great grandfather was doing between 1869 and 1872.
I have managed to find information on the ship he sailed to Australia on.

Boy-Bendixen, Captained by Johan Mathiesen, arrived in Mauritius on 16 October 1868. Boy-Bendixen came from Chincha and Callao (Peru)carrying a cargo of guano (bird droppings) On 15 November Boy-Bendixen sailed for Melbourne arriving on 23 December 1868.
On 18 January 1869 sailed again for Guam.
Information supplied by David Asprey, Lloyds Shipping List.

Boy-Bendixen was a barque built in the Danish town Aabenraa in 1862.The material was Oak and the ship had a loading capacity of 339 tons.In 1871 the home port was Copenhagen, the captains name was Moos and the owner was H.C. Holm. The ship has no registration letters.
The ship was not mentioned in the 1872 or later editions of the Danish Shipping List.