Jack Fish, a novel, by J. Milligan.
Milligan's literary buddies go way out to sea (pun intended) in their blurbs and reviews but, so what? It's a really funny book with a clear eye on the main chance. Of course I liked it. Anything that reminds me of Arthur Curry (AKA Aquaman) I like. I even like Ookla the Mok's song.
I liked Aquaman so much I even like Il Gigante di Metropolis.