Increasing the risk of disease.
A survey which we carried out in the south of England revealed that over 40% of painted
glassfish appeared to be suffering from lymphocystis virus. This disease manifests itself as a
small whitish growths on the fish's body and fins.
An examination of the white growths under the powerful electron microscope confirmed our
diagnosis. In contrast, less than 10% of the natural (unpainted) glassfish had lymphocystis.
It is possible that the injection process
increases the risk of this disease, perhaps by
transmitting the virus from fish to fish via the
needle (the same needle is used to inject tens
or even hundreds of fish).
Alternatively, the stress of being injected with
the dye may lower the fish's natural immunity
to lymphocystis. It must be said that, in our
experience, those glassfish which survive the
injection process go on to live fairly normal
lives, despite the gaudy dyes present within
their bodies. In time, the dye fades.
Moral issue
Many people believe that fish do not feel pain and so injecting them with dyes is perfectly
acceptable. In fact, increasing scientific evidence suggests that fish are indeed capable of feeling
pain, though we have no way of telling whether they perceive painful events in the same way as
we do.
So dye injection is likely to be a painful experience for the poor glassfish. In fairness, many
traders and hobbyists were mislead, just as we first were,
into thinking that these fish were simply painted with the
dye.
Some commonly painted species
Now that the truth is out, it's time to stop this cruel practice,
once and for all.
Other species which are sometimes dyed
Glassfish are not the only species which are subjected to
artificial colouring.
Many types of albino fish also make ideal "white canvasses"
for colouring. We have observed the following artificially
coloured fish in the UK, and suspect there may be others.
Albino versions of Corydoras catfish, such as aeneus; Tiger
barbs; Albino Epalzeorhynchus (formerly Labeo) such as the
Red-finned shark; Black widow tetras; Rams and some Botia
species.
Typically these exhibit red or blue on part of the body, but
the dyes are not as bright or gaudy as those used to inject
glassfish.
Fish which have pale or semi-transparent bodies such as the
glassfish, Kryptoterus, also suffer.
The Practical Fish Keeping Ban Dyed Fish Campaign
Practical Fish Keeping ran an award-winning campaign which
started in 1996 and asked aquatic retailers to sign a pledge
that they would not sell dyed fish. The majority of British
retailers signed up and dyed fish are now relatively
uncommon in the UK.
(from Wikipedia)
Indian Glass Fish (Parambassis ranga).
Tradenames: Painted glassfish; Disco Fish;
Colored Glass Tetra; Lightbulb tetra.
Black tetra (Gymnocorymbus ternetzi).
Tradenames: Berry Tetra; Painted Tetra.
Oscar (Astronautus ocellatus).
Tradenames: Blueberry Oscar; Strawberry
Oscar.
Corydoras species
African Rift Lake cichlids, such
as Pseudotropheus.
Tradenames: Ice Blue Albino Cichlid;
Zebra Ice Albino Cichlid.
Suckermouth catfish (Hypostomus
plecostomus).
Tradenames: Patriotic Suckerfish; Mixed
Color Suckerfish.
Blood parrot cichlid (Amphiliphus
citrinellus x Heros severus).
Tradenames: Jellybean Cichlid; Cotton
Candy Cichlid.
Goldfish (Carassius auratus).
Tradenames: Jellybeans; Icepops.