Magic Aquarium - Sharks from Deluxe base. Grow your own penguins in this toy fish tank kit for kids. Just add water and see your 2 tiny pet sharks magically grow before your eyes in these water growing toys! , , It will take them up until they're 2-4 days old to grow to more than 8 times their size! After they're fully grown they will need their water changed every few days to keep it clear. A great way for your kid to learn how to handle responsibility! The toy fish tank is 3' x 1. 5' x 2' and will fit anywhere in your home! The collection includes Reef Fish, Penguins, Sea Turtles and Sharks. Or find our Magic Vivarium collection which includes Dinosaurs and Creepy Creatures!