Regular pools usually disinfect the water inside of them using chlorine–but not Disney. They use bromine, which is a fancy, more expensive, and much milder smelling chemical (and is not as harsh as chlorine when it hits your skin or clothing).

The iconic scent of the water in Disneyland attractions like Pirates of the Caribbean and it's a small world is the result of a specific chemical treatment process that prioritizes guest comfort over standard pool maintenance. Unlike public pools that use high concentrations of chlorine, which can have a harsh, medicinal odor, Disney uses bromine as its primary sanitizing agent. Bromine is more expensive than chlorine but is much more stable in high-temperature environments and has a distinct, milder, "metallic" or "sweet" ozone-like scent that many guests find nostalgic and pleasant. In 2026, Disney also utilizes advanced filtration systems that remove organic debris more efficiently, preventing the "swimming pool" smell that occurs when chlorine reacts with contaminants. Furthermore, the dark, indoor environments of these rides prevent UV rays from breaking down the bromine, allowing the scent to linger in the humid air, eventually becoming a "sensory anchor" that guests subconsciously associate with the magic of the park.