Anchor Worm (Lernaea)
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About this condition
A parasitic infestation by crustaceans of the genus Lernaea, which embed their head into the body surface beneath the scales. The thread-like body of the parasite may be visible protruding from the fish, causing inflammation and secondary infection at the attachment site.
Common symptoms
- Thread-like or rod-like parasite bodies visible on the body surface
- Redness and inflammation around the attachment site
- Fish rubbing against substrate or decorations
- Loss of appetite and abnormal swimming behavior
Common causes
- Parasitism by crustaceans of the genus Lernaea
- Introduction via outdoor-raised or unquarantined fish and aquatic plants
- Weakened immunity due to water quality deterioration
- Stress from overcrowding
Prevention (husbandry & daily care)
Thoroughly quarantine newly introduced fish and aquatic plants, and take care when introducing outdoor water or live food into the tank. Maintain stable water quality management to support the fish's immune system.
Related species guide
→ Browse the species guide for this animalWhen to see a vet
Consider consulting a specialist store within a few daysWhat can a specialist store do?
A specialist aquarium store will assess the degree of infestation and the presence of secondary infection, then advise on the removal approach and treatment of the whole tank. Physical removal of the parasite carries infection risks, so it is preferable to proceed under expert guidance.
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