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[0] Virus [1] Lymphocystis [2] White, nodular growths extending from fins or skin [4] Avoid adding the water from the bag of new fish into your aquarium, and discard the water in the fish bag. Quarantine new fish before adding them to your aquarium in a separate isolation tank. Avoid feeding virus-contaminated live food; use anti-bacteria-medicated fish food. [3] 
Affected areas can be treated with topical disinfectants; add Formalin solutions to water.
Diagnosing Fish Ailments: How To Analyze and Treat Problems. | PetSmart
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