Is salmon a saltwater fish? Or is it a freshwater fish?
In the sea, there were a lot of colorful ocean fish swimming around.
There is a wide variety of saltwater fish at the aquarium, but the staff said we’re not allowed to eat any of them.
An ocean fish is simply an ocean fish. They also happen to be the most delicious kind of fish.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.