Lu Chengzhou is reborn back to the day when his wife and daughter are cornered at the door by debtors, accidentally discovering that his ancestral broken fish tank leads straight to the Dragon Palace. In his past life, he neglected his family and tragically lost his wife and daughter. In this life, relying on the Dragon Palace to obtain dragon pearls and water-controlling divine power, he catches dragon carp and retrieves gold sand to clear his debts and protect his family, makes a fortune through seafood treasures, punishes evildoers, helps relatives and friends fulfill their dreams, and ultimately builds the Canglan Ocean World, always putting companionship with his wife and daughter first to guard the fulfilled family he missed in his past life.