Signs Of Infection

Worms up to 20mm long, 1-2mm wide clinging to the fish's body.

Fish Affected

Anchor worms (Lernaea sp.) usually only affect pond or outdoor fish such as Goldfish and Carp however, Minnows and some Cichlids may also be affected.

Details Of Infection

The Anchor worm's life-cycle begins with larvae hatching from eggs in the water. The larvae is free swimming until it finds a suitable host where upon it attaches itself to the gills. Here, the larvae mature and breed after which the males stop becoming parasitic and leave the fish. It is the females that reattach themselves to the host and develop into the worm-like parasites which can be seen clinging to the fish's body.

It is in the spring when the females lay their eggs after which they either die or produce subsequent broods. As the females die, they leave openings on the host's skin which often allows a secondary fatal infection to enter.

Treatment

Adult worms can sometimes be physically removed individually but this is a very stressful process. Often the most effective treatment is a salt dip or commercial chemical remedy. To fully eradicate the anchor worm parasite one must remember to attack both the adult and the free swimming larvae to prevent reinfection.