Painted fish
Artificially colored aquarium fish with temporary, controversial dye methods.
Painted fish are ornamental aquarium fish that have been artificially colored through methods such as dye injection, dipping in dye solution, or feeding dyed food. This controversial practice, also known as juicing, is intended to make fish more attractive to consumers, but the coloring is not permanent and typically fades within six to nine months. It is distinct from genetic modification, which produces permanent, heritable coloration.
- Mortality rate
- reported to have a very high mortality rate
- Color fade time
- six to nine months
- Lymphocystis infection rate painted
- over 40%
- Lymphocystis infection rate unpainted
- 10%
- Campaign start year
- 1996
- Campaign publication
- Practical Fishkeeping
Lore & Background
The practice of painting fish involves several methods. A common method is dye injection via hypodermic syringe, with fish typically injected multiple times. Alternatively, fish may be dipped in a caustic solution to strip their outer slime coat, then dipped in dye. These methods are reported to have a very high mortality rate. Fish can also be tattooed using a low-intensity laser with dye, a process originally developed for fisheries. Hormone administration can increase coloration but may render female fish infertile. Some species commonly painted include the Indian glassy fish, black tetra, Oscar, Corydoras species, African Rift Lake cichlids, suckermouth catfish, blood parrot cichlid, and goldfish. Most dyed fish are albinos, except for the Indian glassy fish.
Reader's Guide
The significance of painted fish lies in the controversy and health concerns surrounding the practice. A 1998 survey in the South of England found that over 40% of painted glassfish showed signs of Lymphocystis infection, compared to 10% of unpainted glassfish. The infection may have been caused by virus transmission via infected needles or reduced resistance due to stress. Injected fish often die without apparent external symptoms, presumably from kidney disease. Efforts to stop fish-painting include a campaign by Practical Fishkeeping starting in 1996, which led to a significant decrease in sales in the United Kingdom. The RSPCA regards the practice as cruel and unnecessary cosmetic mutilation. Campaigns in Australia and the UK have limited sales, but dyed fish are still available, generally imported from Southeast Asia. In February 2006, the UK's Defra confirmed it would not make selling dyed fish illegal under the Animal Welfare Bill. The legacy of painted fish is a cautionary tale about animal welfare in the aquarium trade, with ongoing debate and partial regulatory success.
Did You Know?
- Painted fish are also known as 'juiced' fish.
- A 1998 survey found over 40% of painted glassfish had Lymphocystis infection.
- The coloring of painted fish fades in six to nine months.
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