is one piece episode 55 filler?

Having entered the Calm Belt, the Going Merry ends up on top of a Sea King's head and is surrounded by other Sea Kings, Zoro suggests that nobody should move or make a sound and hope that the beasts ignore them so they can paddle back. Usopp, in fear, shouts at the suggestion, which a Sea King hears causing it to attack the ship.

Apis falls off the ship but is rescued by Luffy before she is swallowed. She notices that Luffy's arm stretched when he rescued her.

While being pulled up to the ship, she sees the Sea King's nose and asks Luffy to swing her back downwards.