Trichodina

Symptoms

Spotting illness early gives the best chance of a cure, so check your fish daily at feeding time. Excess slime, flashing and rubbing, clamped fins, faded colour and irritated gills. The parasite is only seen under a microscope. If you see several of these signs together, act promptly rather than waiting.

Causes

A saucer-shaped protozoan that lives on the skin and gills and multiplies in dirty, overstocked tanks with organic build-up. 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

The key fix is excellent water quality and reduced organic waste; severe cases are treated with an anti-parasite medication. Vacuum the substrate well.

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 and substrate clean, avoid overstocking, and quarantine new fish. 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.