The details of what he ate and drank vary somewhat across reports. Most accounts mention the Coca-Cola. Some mention the sardines as a separate find. The specifics — whether he drank the entire Coca-Cola or rationed it, whether the sardines were consumed or merely found — are not uniformly established across the available reporting. What is consistent is that he had some food and at least one drink in the hours of his confinement.
He also found materials to work with for the practical challenge of staying out of the water. He described pulling wall paneling off interior surfaces to build a platform — a raised surface that would keep at least part of his body above the waterline, reducing the rate at which the cold seeped into him and slowing the onset of hypothermia. The construction of this platform, improvised from whatever materials he could find in the dark by feel, represents a practical problem-solving capacity under conditions of extreme stress and near-total sensory deprivation.
Crawfish were in the water with him, and they were picking at his skin. He has mentioned this detail in interviews — the crawfish in the dark water, feeding on what they found in the wreck. It is one of the details that makes vivid the physical reality of his situation: not just dark and cold, but alive with small organisms conducting their own business indifferently around him.
He armed himself with a plank of wood against larger threats — sharks, barracudas — that he feared might enter the wreck. This precaution was probably unnecessary in a fully enclosed wreck at 100 feet, where large predatory fish are unlikely to navigate, but it reflects the specific content of his fear: the dark water below him was not empty, and his knowledge of what it might contain was limited.