One Pace — Fishman Island 1

One Pace Fishman Island episode 1 ("Into the Depths! The Kraken and the Caribou Pirates") covers manga chapters 603–604.

Into the Depths! The Kraken and the Caribou Pirates

One Pace

Fishman Island 1Into the Depths! The Kraken and the Caribou Pirates

Manga chapters

Chapter 603
Chapter 604

Source anime episodes

Episode 523
Episode 524

What One Pace is

One Pace is a fan project that re-edits the Toei anime to match the manga's pacing. It cuts filler, recaps, and stretched scenes, so a single One Pace episode usually covers the same ground as several broadcast episodes — here, chapters 603–604 re-cut from anime episodes 523–524.