Page 226 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

224 MARINE FISH: ILLNESS AND TREATMENT

Health concerns No sign of injury or any
scarring over the surface of
the body or the fins Bright coloration
and pattern
Most marine aquarium fish are natural inhabitants Fins intact, with
Eyes display no tearing
of coral reefs, which are among the most stable and no signs of
cloudiness
unchanging of all ecosystems on the planet. Many of
the health problems suffered by marine aquarium fish
therefore stem from fluctuations in water quality in
Swims without
the home tank. Maintaining suitable water conditions difficulty Body appears plump,
rather than saggy
will keep the fish in the best condition to repel A healthy fish appears active and feeds well. This Blue Tang
(Paracanthurus hepatus) demonstrates what to look for in
pathogens and parasites. a well-kept specimen.

Health problems can also occur when changes take place in
Overgrown teeth the environment (see opposite). In a reef tank, for example,
make eating difficult, corals rapidly take up elements such as calcium, which they
leading to a loss of
condition incorporate into their hard skeletons. The depletion of
calcium affects the health not only of corals but also of other
tank inhabitants, so regular monitoring and partial water
changes help to maintain a healthy environment.
Choosing fish
Most problems can be avoided by careful selection at the
outset. Avoid individuals with any signs of ill health; juveniles
Appropriate food are preferable to mature individuals, which are hard to age
is essential for good health. and therefore may be very old and more susceptible to illness.
Pufferfish deprived of their natural,
hard-shelled invertebrate foods Young fish acclimatize better to aquarium life and are more
soon develop long, overgrown teeth. likely to be compatible with their tankmates.

Isolation and establishment
A long-established, well-maintained marine tank rarely
succumbs to disease. Most health problems experienced by UNWANTED GUESTS
marine fish are seen when a tank is immature, or when new Many organisms “hitch a ride” into your tank when you acquire
animals or plants are introduced, along with unwanted new fish, rocks, invertebrates, or algae. Some of these unwanted
pathogens. Marine species are vulnerable to a range of guests can be seen with the naked eye; most will die or be eaten
bacterial, viral, fungal, and especially parasitic diseases, which by your fish, but some can be a nuisance and should be removed.
spread quickly if fish are kept in suboptimal conditions— MANTIS SHRIMP BRISTLEWORMS
for example, during transportation. For this reason, newly These predatory crustaceans will attack Similar in appearance to caterpillars,
desirable invertebrates and fish in
these worms will attack mollusks in
acquired fish should always be transferred to a separate tank for the tank. They have claws capable of the tank. Take care when removing—
two weeks before entering the main tank. This isolation tank cracking open the body casing of crabs. these worms have sharp spines.
should be set up and run from the outset in parallel with
the main tank. It need not be large, and tank decor should be
kept to a minimum for ease of cleaning. The fish in the
isolation tank should be fed well and encouraged to take
foods such as marine flake, which contain all the key vitamins
and minerals. When you are satisfied that the fish are well
nourished and free from disease, they can be transferred
carefully to the main tank.

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