Page 56 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

54 FRESHWATER FISH: ILLNESS AND TREATMENT

Health concerns

Eyes are bright
and must Body appears plump,
not appear rather than saggy
swollen
Fish are susceptible to a wide range of bacterial, viral,
fungal, and parasitic diseases. The artificial conditions Scales evenly cover the
body and must lie flat
in the aquarium tend to concentrate the risk of disease
and increase the speed at which illnesses spread, because
fish health is strongly influenced by the quality of the Gill movements Fins and tail
may increase should not
environment. Early intervention can head off many of under stress normally be
ragged at the
the most common conditions, but, as with humans, A healthy fish appears active and feeds well. This Cockatoo edges
Dwarf Cichlid (Apistogramma cacatuoides) demonstrates
prevention is always better than cure. what to look for in a well-kept specimen.

Risk factors
A fish housed alone is less likely to succumb to illness than
one in a community aquarium because it is not subject to
bullying by tankmates. This often causes minor injuries, such
as damaged fins and scales, which may then become infected.
Aggression usually increases at the beginning of the spawning
period, so a close watch should be kept on fish at this time.
The greatest risks to health occur when fish are introduced
to the aquarium. New acquisitions should be held in a simple
Minor injuries, such as the rip in the Fungal infections are opportunistic, isolation tank for two weeks before transfer to the main tank,
dorsal fin of this corydoras catfish, lurking in the tank and invading at by which time any serious health problems should have
can provide an entry point for sites of injury. If untreated, they
life-threatening infections. spread fast and may kill the fish. emerged. With new fish, it is often helpful to remove all the
occupants from the tank, rearrange the tank decor, then
Get to know your fish introduce new fish together with the previous occupants.
Most common diseases of aquarium fish are treatable, This strategy significantly reduces outbreaks of bullying.
provided they are identified in their early stages. Later in
the course of a disease, obvious symptoms, such as major
color changes or large parasites, will become apparent, WHITE SPOT
but it may be too late for successful intervention. The best White spots on the
strategy for disease prevention is therefore close observation; fish’s body contain
mature protozoan
knowing how your fish look, feed, swim, and interact with Tomites in the parasites
others allows you to spot subtle changes in appearance and water find new The spots rupture,
fish to attack
behavior that may signal stress or the early stages of disease. releasing parasites
If you suspect that a fish may be ill, check the tables on into the water
pages 56–58 and attempt a diagnosis. If in doubt, consult an The cysts break
open, releasing
expert at your local aquarium store. Move the affected fish tomites into
out of the main tank into a hospital tank (see opposite) for the aquarium
further observation and treatment. This will isolate the fish Parasites
from its tankmates and prevent cross-infection. Always check Each cyst can form cysts
the quality of water in the tank; dirty or unbalanced water produce up to 1,000 Cysts sink and attach to
may cause illness directly or put the fish under stress, thus tomites, which are the aquarium floor
the free-swimming
predisposing it to attack by pathogens that may already be in form of the parasite
the tank. Most healthy fish carry a natural burden of parasites,
but environmental stress may lower the immune resistance of Protozoan parasitic infections, such as white spot (also known as “ich”),
spread fast within the aquarium. The life cycles of the parasites are
the fish and allow the parasites to multiply. completed rapidly, and thousands more can be produced in a single cycle.

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