BACTERIAL DISEASE

Most cases of bacterial disease are secondary infections, caused by poor water quality or parasite infestations. The koi is protected against bacterial infections by its mucus. If the mucus is damaged by poor water quality for instance, the koi could become infected by bacterial disease.

Other possible causes of bacterial infection are if the koi is damaged against a rock for instance.

Ulcers are a common form of bacterial infection, these are often preceded by raised scales. Treatment at this point with a suitable anti-bacterial spray can often halt the progression of ulcers.

TREATMENT

The first step is to check the primary cause of the problem. After correcting water quality values and treatment of parasites wounds caused by bacteria can be cured.

For raised scales and small wounds, treatment with a suitable medical kit such as the the Kusuri Ulcer Wound Kit may be sufficient. In more serious cases treatment with antibiotics is needed. The best way to treat with antibiotics is by injection. To obtain antibiotics the koi may need to be treated by a vet.

Virtually all cases of fin rot are caused by stress, fear or poor environmental conditions. Fin rot is quite often one of the first signs that a fish disease problem exists and all water parameters should be checked.
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Ulcers can be quite common with Koi, common causes are poor water quality and secondary infection following parasite infestation or damage caused by scratches etc.
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Fish gills are extremely sensitive and can be susceptible to parasite, bacterial and fungal diseases.
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There is no actual disease called Dropsy, it is a clinical description of the condition which is often a secondary infection. also known as Pine Cone disease the fish's body swells up, eyes can bulge out and scales are raised.
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Raised scales on Koi and other fish can be an early sign of infection, early treatment may prevent the infection developing into a more serious condition such as an Ulcer.
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