The Aquarium Cars (briefly known as the Light up Aquarium Cars) are used to deliver sea life to the Aquarium.
- 2001-2003 (square red and blue tanks)
- 2004-2010 (cylindrical tanks)
- 2011-2012 (light-up version, octopus replaced with squid, shark replaced with hammerhead shark)
- 2013-2017 (silver magnet casing)
- 2018 (Unpainted chassis and edges, neon green wheels, wooden flatbed with removable lavender hammerhead shark and plastic cover, plastic tanker with lavender stingrays and light blue magnet casing)
- The liquid in the original version tended to leak after a few months of use due to the fragile nature of the wood surrounding the tank windows.
- The Clown Fish Cars from the Aquarium Set are a lighter shade of blue than the 2004-2010 aquarium cars.
- The 2001 Prototype cars are the same length as Neil and Lady, whereas the released 2001 cars are the same length as Annie and Clarabel.