Sea Route 20 — Pokémon HeartGold & SoulSilver

Every wild Pokémon here, by encounter method.

Sea Route 20 lists 6 Pokémon across 4 encounter methods (surf, old rod, good rod, super rod), between level 10 and 40.

Sea Route 20 in the official games

The original game's table for this area:

Surf Lv 30-35

Old Rod Lv 10

Good Rod Lv 20

Super Rod Lv 40

Open in the interactive guide