Painted fish are ornamental aquarium fish which have been artificially coloured to appeal to consumers. This artificial colouring, also known as juicing, is achieved by a number of methods, such as injecting the fish with a hypodermic syringe containing bright fluorescent colour dye, dipping the fish into a dye solution, or feeding the fish dyed food.
This controversial process is usually done to make the fish a brighter colour and more attractive to consumers. The colouring of the fish is not permanent, and usually fades away in six to nine months.