Fish Tuberculosis

Symptoms

Spotting illness early gives the best chance of a cure, so check your fish daily at feeding time. Long-term wasting, a hollow belly, curved spine, skin sores or ulcers, loss of scales and fins, and slow deaths over weeks. Hard to cure. If you see several of these signs together, act promptly rather than waiting.

Causes

A bacterial infection (Mycobacterium) that spreads slowly through contaminated water, equipment and by fish eating infected bodies. It thrives in dirty, stressed tanks. In nearly every case 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

Very difficult to treat; most keepers focus on excellent water quality, removing and euthanising badly affected fish, and not spreading it via shared equipment. Some antibiotics may slow it.

While treating, increase aeration, remove activated carbon from the filter (it absorbs medication), finish the full course even after the fish looks better, and keep the water immaculate with regular changes. Always dose for the tank's true water volume and follow the product instructions.

Prevention

Keep water pristine, avoid overcrowding and stress, quarantine new fish, and never let fish eat dead bodies. The golden rules are simple: quarantine every new fish for 2-4 weeks, never overstock or overfeed, avoid sudden temperature or chemistry swings, and do regular partial water changes. A stable, clean, low-stress aquarium prevents the large majority of disease.

FAQ

This information is general guidance, not veterinary advice. Consult an aquatic vet for serious cases.