Fish diseases

Fish diseases are usually caused by bacteria, viruses, parasites or worms. If fish are infected, it is important to study the symptoms well and to determine, what disorder fish have. A diseased fish can be recognized by its listless behaviour or by spots on its skin. Different symptoms of fish diseases can be rubbing its skin against the pond bottom or other deviating behaviour. The most common diseases include:

White spot Koi herpes Trichodina
Carp louse Hexamita Chilodonella
Gill worm Saprolegnia Fish tuberculosis
Tape worm Costia Oodinium
Skin worm Protozoa Fin rot
Carp smallpox Cryptobia Swollen belly dropsy

In ponds fish diseases do not occur very frequently. However, there are a few riskful moments:
If you introduce new fish to a pond, it may happen that one of the new fish is sickened for some illness as a result of which it will also infect other fish.
After winter you can find diseased fish, because during that period fish have lower resistance against illness.

Treating fish diseases

In general diseases in pond fish can treated well. It is always wise to put diseased fish in quarantine outside the pond. In spite of the fact that many fish diseases are not directly contagious, you will prevent in this way that diseases involved will spread in the pond. Different kinds of medicine are available for several kinds of diseases. It is better to prevent fish diseases. Below we are giving you a few tips how to prevent diseases among pond fish:

  • To prevent fish disease after winter, it is important to keep resistance of fish to the level during the winter months. To achieve this you should distribute good quality of feed during the summer months, containing all important nutrients such as vitamins and minerals.
  • Regularly inspect the water quality of the pond water. Special water test kits have been developed for this purpose, enabling you to measure quality simply and quickly.
  • A different important measure to prevent fish diseases is to filter the pond water using a pond filter equipped with activated carbon. The activated carbon will absorb any pollution from the water, by which fish diseases can be prevented.
  • Do not introduce too many fish to your pond. The directive is 50 cm of fish length per 1,000 litres of water.

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