Hi all,
I've been recently researching Charles J Anderson as part of my own family history, and it appears that there are in fact two C. J. Andersons within the wider Auckland region at the time.
By the sounds of things Darrell, the first Charles Anderson is probably the Charles that lived in Ponsonby, married Bella Owsley and drowned in the surf, as he seems to have been a master mariner for his entire life which would be consistent with your statement that both John and Charles were master mariners.
The second Charles John Anderson (my ancestor) was born in Goteborg in 1866 to Carl Anderssen and Johanna Holson (your Hannah Olson?). It is likely that he moved to New Zealand in 1885, based on statements made in his sons' war records (5 of his children fought in WW1), and married Mary Jane Thornally in 1888. This Charles was a contractor and later a sawmiller out at Te Kopuru, near Dargaville, described as "earning a crust"
in the bigamy trial of Walter H. Bassett in 1913. The Andersons did finance a timber barge as part of their sawmilling business, but beyond this I cannot find any evidence that this Anderson had any kind of life at sea.
Hopefully this goes some way to clarifying potential confusions between the two Charles Johns and their parents that have arisen in this thread.