6ddd20e8_Common_diseases_of_goldfish__Treatment
[Disease and Causes] White spot Caused by Ichthyophthirius multifiliis parasite [Symptoms] Small white spots, about the size of a salt grain, on the skin, fins and gills. [Reason for Infection] Stress related. Usually a consequence of poor or incorrect water conditions, fluctuating temperature and general poor husbandry. Sensitive species may develop white spot as a result of being introduced to a new aquarium. [Action] Ensure the water is free of pollution and isolate cause of stress. [Treatment] 
Treat promptly with an anti-parasite medication. It may be necessary to raise the water temperature to improve the effectiveness of the treatment. Wounds left by parasites may become secondarily infected.
Common diseases of goldfish
Treatment