Signs Of Infection

A whitish film covers the skin primarily around the head and dorsal fin. If the film covers the gills, the fish's respiration rate may be increased. Affected fish also rub on hard objects such as rocks or the substrate. In the latter stages of the disease the skin will appear swollen and begin to fall away and the fish may have difficulty swimming.

Fish Affected

Chilodonella, Chilodonella cyprini, is widespread and affects all tropical aquarium fish particularly if injured.

Details Of Infection

The film is cause by a single cell parasite covered in hairs which enable it to swim. The parasite initially attacks injured fish but in crowded aquariums will host on healthy fish slowly debilitating its host. Dead fish must be removed quickly as the cell leaves the body within two hours.

Treatment

Commercial chemical remedies are available but an equally successful treatment is a strong (3%) salt dip. Keep the fish in the salt dip until they roll over then transfer them back to the aquarium. A less stressful alternative to this is a 1% salt solution for around 10 minutes then return the fish to a clean, preferably warm (82-86°F) aquarium. One must remember that the parasites may remain free swimming in the infected aquarium and these must be dealt with to prevent reinfection. The parasites will die if left in a fish free aquarium for 5 days at 86°F.

Also ensure that good water quality exists and the water is well oxygenated.