Minecraft wiki entry for Pufferfish, associated text: In Java Edition, pufferfish spawn in groups of 1-3 in warm, lukewarm and deep lukewarm ocean biomes. In Bedrock Edition, fish spawn underwater at around 12–32 blocks away from the player in groups of 3–5 in warm ocean biomes. Pufferfish spawn only on the surface; that is, there must not be a spawnable block above the spawn location with a non-solid block on top.