Dropsy
Symptom (often bacterial/organ failure)
Critical severity
A symptom, not a single disease — fluid build-up causing a swollen body and raised 'pinecone' scales.
Symptoms
Early recognition is the key to a good outcome, so inspect your fish daily at feeding time. Severely bloated abdomen, scales sticking out like a pinecone, bulging eyes, lethargy and loss of appetite. If you notice several of these signs together, act promptly rather than waiting.
Causes
Internal bacterial infection or organ (kidney) failure causing fluid retention, frequently linked to chronic poor water quality or old age. In almost all cases the underlying trigger is stress, poor water quality or the introduction of an infected fish, all of which weaken a fish's natural defences.
Treatment
Isolate the fish, perform water changes, and treat with a broad-spectrum antibacterial; Epsom salt baths can help draw out fluid. Prognosis is poor once pineconing appears.
Throughout treatment, increase aeration, remove activated carbon from the filter (it absorbs medication), complete the full course even after symptoms fade, and keep the water immaculate with regular changes. Always follow the medication's dosing instructions and dose for the tank's true water volume.
Prevention
Maintain excellent water quality, avoid overfeeding, and quarantine new fish to prevent the underlying infections. The golden rules are simple: quarantine every new fish for 2-4 weeks, never overstock or overfeed, avoid sudden temperature or chemistry swings, and perform regular partial water changes. A stable, clean, low-stress aquarium prevents the overwhelming majority of disease outbreaks.
FAQ
Can dropsy be cured?
Is dropsy contagious?
How serious is Dropsy?
Can Dropsy be prevented?
Will my other fish catch Dropsy?
This information is general guidance, not veterinary advice. Consult an aquatic vet for serious cases.