Goldfish

Freshwater Tropical

Fin Rot

Progressive deterioration of fin tissue caused by opportunistic bacteria — usually a symptom of poor water quality.

Mild

Freshwater Tropical

Dropsy

Bloated body with pinecone-stuck-out scales — a symptom of organ failure, not a disease itself. Prognosis is generally…

Critical

Freshwater Tropical

Swim Bladder Disorder

Loss of buoyancy control — fish floats, sinks, or swims at odd angles. Common in fancy goldfish and…

Moderate

Freshwater Tropical

Cloudy Eye

Hazy or opaque film over one or both eyes — usually a sign of bacterial infection or chronic…

Moderate

Freshwater Tropical

Branchiomycosis (Gill Rot)

Fungus (true fungus) disease of aquarium fish. Key signs: rapid breathing, gasping at surface, gill necrosis with white/marbled…

Severe

Freshwater Tropical

Costia (Ichthyobodo)

Parasite (flagellated protozoan) disease of aquarium fish. Key signs: blue-grey film of mucus over skin ('slime disease'), peeling…

Moderate

Freshwater Tropical

Trichodina Infestation

Parasite (ciliate protozoan) disease of aquarium fish. Key signs: excessive mucus (slime coat), pale or 'milky' patches on…

Moderate

Freshwater Tropical

Fish Lice (Argulus)

Parasite (branchiuran crustacean) disease of aquarium fish. Key signs: flat, round, 5–10 mm semi-transparent lice visible attached to…

Moderate