is one piece episode 231 filler?

The men who raided the ship reveals themselves to be a group of bounty hunters known as the Franky Family. Zoro defeats the bounty hunters easily using the Nitoryu Sai Kuru move.

At the gold exchange, the Straw Hats exchange their gold from Skypiea for money. Surprised at how much gold was exchanged, the teller consults the owner, who takes them to the VIP room to inspect the gold.

Due to the historical value of the gold, the appraiser gives 300 million beli. Upon walking out of the gold exchange, they are overheard by the Franky Family.