@foone Maybe "oceanus pacificus" should be a genative here ("of the pacific"). So "oceani pacifici". I believe two nominative nouns following each other implies they have the same referant. Swapping the word order to have the genative at the end might be more natural, but either is correct.
"Oestrus electrumque pacificus" could work too, maybe. (Not sure if "-que" would be natural or odd here as an alternative to "et".) Like "senatus populusque romanus".