When It All Goes Wrong
Despite the best of
care all fish will at some time experience some illness or injury. Here are
descriptions of some of the more common ailments and some ideas on their care.
Most treatments are poisons which attack the cause of the illness, but
overdosed, they will attack your fish. Always follow the manufacturers
instructions.
Any time you do have
a problem, check your water quality. Poor water quality is the single biggest
stress for fish and stressed fish are more prone to infection than healthy
fish. Ammonia and nitrite should ALWAYS be zero, nitrate below 15 and pH and
hardness should suit the fish you are keeping.
Whitespot | Velvet | Fungus | Dropsy | Fin rot | Popeye
| Swim Bladder
| TB
Visible
Problems
(Icthophthirius
multifiliis)
The UK name,
whitespot, describes the problem exactly. The fish will have white, pinhead
sized spots on the body and fins. This is a parasite. It penetrates the fish's
skin and feeds from the body fluids. After a time it drops from the fish to the
substrate as a hard cyst. In this state it reproduces thousands of new
parasites which then break free and swim off to find a new victim. In the
confines of an aquarium this of course can be the same fish again, only worse.
Treatment. The
parasite is at its most vulnerable in the free swimming stage. There are a
number of remedies available commercially. Some of these require treatment over
a period of time to ensure that all the cysts have hatched and all the
parasites are destroyed.
(Oodinium
pillularis)
Another parasite,
velvet appears as a yellow grey haze across the skin. The gills can also be
affected. Life cycle of the parasite is similar to whitespot. Velvet and
whitespot can lie dormant in the aquarium until conditions deteriorate and
stressed fish become vulnerable. Healthy fish can and do resist infection in
the initial stages.
Treatment. There are
several proprietary remedies available.
(Saprolegnia
and Achylya species)
Fungi are primitive
plants that grow on dead or decaying organic matter. They can be found in the
aquarium where there is uneaten food, dead animals or fish and even growing on
bogwood. Healthy fish are not affected but where there has been damage to the
tissues, like wounds to the body or fins, then fungus can infect these areas.
It is visible as a streaky cotton wool like growth on the body or fins. Poor
water quality will make fish more susceptible to infection of even minor
wounds.
Treatment. Aquarium
salt can help but specific anti-fungal remedies are very effective.
(Aeromonas
and various other bacteria)
The fish's belly
becomes swollen, often to the point where the scales stick out from the skin,
giving a pine cone appearance to the affected fish. Fluid retention and build
up in the body can stress the heart and cause the eyes to pop out.
Treatment. This can
be difficult and is not always effective. There are some proprietary remedies
available. Adding aquarium salt at about 3grms/quart to the water can help to
relieve the pressure by altering the osmotic pressure around the fish.
(Aeromonas and
various other bacteria)
In this instance the
bacteria attack the fin membrane and rays. Pieces of the fin membrane discolour
and then come away. The rays are also attacked. If this reaches the body the
fish will normally die. Fins damaged due to nipping or poor handling when
netting are susceptible to infection. Rapid treatment is most effective.
Treatment.
Proprietary remedies work well. For coldwater fish ensure a minimum temperature
of 61F.
(hyphothalmus)
May occur as a
symptom of other problems e.g. fluid pressure due to dropsy, or a sign of
bacterial or parasitic infection. If the cause can be established, treat with
anti bacterial or anti parasitic remedies.
Less
Visible Problems.
The swim bladder is
a gas filled sack within the fish. The flotation effect allows the fish to
achieve neutral buoyancy, so maintaining its position in the water. Damage or
infection may cause the fish to float or sink and it will have difficulty
remaining stable as it swims. Fancy goldfish, with their compressed bodies are
often affected as the swim bladder is compressed too.
Treatment. Due to
the variety of reasons for difficulties there is no one, simple cure. Anti bacterial
treatment sometimes work, adding aquarium salt to the water can help relieve
the effects.
Affected fishes can
become shy and nervous and may go off their food. In the later stages they will
appear thin. Loss of colour, skin defects and curvature of the spine may also
be present. This condition can (but rarely does) affect humans so avoid
swallowing water and exposing open cuts or grazes to aquarium water. In humans
infection will produce itchy sores on the arms and body. These are difficult to
get rid of and will be recurrent.
Treatment. Some anti
bacterial remedies available through veterinarians are effective in the early
stages where a conclusive diagnosis has been made. Generally it is better to
dispose of the fish as corpses will be cannibalised and this will spread the
infection. The best preventative is good water conditions.