Besides the loss of his family possessions, what else did Pi lose When the Tsimtsum sank in Life of Pi? What did he gain?

When the Japanese cargo ship Tsimtsum sank, Pi Patel lost much, but he gained a little, too. Besides his family's possessions, including most of the zoo animals they were transporting to Canada, Pi lost his mother, his father, and his older brother, Ravi. This was certainly the most grievous loss that he experienced. In addition, he lost the unvarnished optimism of youth. At only sixteen years of age, Pi had known difficulties in life—including the teasing he endured at school because of his name and the sorrow of having to leave his friends when his family decided to move to Canada—but he had never known tragedy. Once a person has lived through a great loss, their innocent joie de vivre dissipates. He lost his future as it had been envisioned by him and his parents. One might even say he lost his boyhood since his experience required him to grow up fast.
Alone at sea, adrift on a lifeboat with a 450-pound Bengal tiger, what could he have to gain? The fascinating part of the book is that it shows that Pi did benefit from the sinking of the ship despite his massive losses. He gained resilience as he sprang back again and again from life-threatening peril and emotional despair. He gained self-confidence as he learned to rise to an overwhelming challenge and even become master—to some degree—of a ferocious, carnivorous beast. He gained greater faith in God as he put his trust in the Creator during his long, lonely voyage. He gained a new identity since no one could endure such an ordeal without changing radically because of it. And he gained an incredible story to tell—two of them, in fact—in case people chose to disbelieve one or the other.
Pi's physical and emotional losses from the shipwreck were severe, but he achieved some intangible gains in their stead.