The noun fish is a considered the singular and plural form, although fishes is accepted by some. The possessive form is fish's for the singular or plural. Example sentences:
My fish's name is Oscar.
Marlin, Dory, Nemo, and Gill are the fish's names in the movie 'Finding Nemo'.
You could use '...the fishes' names in the movie...', it would be pronounced the same but it is not a universally accepted form.
When eating fish, I prefer salmon; but nothing beats fishing and catching a trout.
the fish has gills
Fish is my best delicatessen..
In some cultures, jawless fish are a delicacy.
I flayed the fish, for example.
the fish was born demented.
Some fish have caudal fins.
I have deca fish! I ran a triangulation
Noun: That fish was extremely heavy. Verb: How do you know how to fish?
I saw fish swiming toward midsteam.
i gave a denomination to my pet fish today
The cormorant sought fish in the blue ocean.
This fish is so abnormal.