"... It was this sad state of things which made it necessary to bring the Galaxy 'down'. This is reminiscent of the detail in the Jewish tradition about Eben Shetiyyah, that the waters sank down so deeply that David had to recite the 'fifteen songs of ascension' to make them rise again ..."

The Galaxy, being a kind of river, would provide the necessary water to refill the sea. Suddenly we have improved our understanding of Aa6-66, where Metoro said that the Galaxy (Goe) 'went asleep' (moe):

Aa6-64	Aa6-65	Aa6-66	Aa6-67	Aa6-68	Aa6-69	Aa6-70
i to moa	ko te vai hopu o te moa	e he goe kua moe	ki to vaha o to ika mea	o te maitaki	kua noho te ariki	e mago

The Galaxy 'went asleep' because it disappeared from the sky. Also the Tahua creator identified, it seems, the Galaxy with a source of water (cfr vai in Aa6-65).

In Aa6-67 the 'red fish' (ika mea) also disappears because water from the river in the sky is refilling the dry bottom of the ocean deep down - ki to vaha o to ika mea ('into the mouth of the red fish'). Metoro is using the old article to instead of te, he is citing from the old tradition.