Anchor Worm on Goldfish: Causes, Symptoms & Treatment

Anchor worm on goldfish is a small parasite that attaches to the fish skin and burrows into its tissues. The worm feeds off the fish’s blood and tissues and can cause significant damage over time.

Goldfish anchor worm is one of the most common types of worms found in fish tanks. Anchor worm is most commonly found on tropical goldfish, but it can also be found on other types of fish.

They can cause secondary infection and even death. There have several cures for anchor worms, but prevention is the best way to go.

Keep your goldfish clean and healthy by avoiding infected fish, and removing any worms you see.

Anchor Worm on Goldfish

What Are Anchor Worms?

Fish anchor worm is a type of parasitic crustacean that attach themselves to the skin and flesh of fish, causing damage and irritation.

They are named after their distinctive appearance, which resembles an anchor or a tiny stick with a forked tail.

Anchor worms can infect a wide range of freshwater fish, including koi, goldfish, and other ornamental fish.

The widespread freshwater copepods called Lernaea cyprinacea (anchor worm) are found in various aquatic hosts, including fish, tadpoles, and aquatic creatures.

Female anchor worms burrow into the skin and flesh of the fish, leaving only their tails exposed.

Adult-only, the female lernidae is parasitized on both fish skin, gills, fins, eyes, and even inside the mouth cavity and nostril, reacts favorably to the abdomen and the base.

What Causes Anchor Worm on Goldfish

The causative agent of anchor worm in fish is lernaea. Lernaea is a crustacean parasite that lives in the small intestine of fish.

Anchor worms grow so large because they feed on small particles in the water.

If the water quality is bad, the fish will struggle to find food and eventually turn to digest their flesh, including anchoring themselves to objects in the tank.

Anchor Worm Life Cycle

Lernaea has nine stages in the life cycle, including three naupliar stages, five copepodid stages, and one adult stage.

Lernaea specializes in having a direct life cycle (do not need to pass through an intermediary host).

It takes 18 to 25 days to complete, and the life cycle of this species may only be completed through understanding the development or maturing of the organism.

Within 24 hours, the mature female starts releasing eggs from its rear (back) end. Within 24 to 36 hours, an egg hatched from each egg released.

Females are prolific and can produce batches of 250 young (nauplii) every two weeks for up to one year at temperatures above 25 degrees Celsius.

Newly hatched nauplii are parasitic and develop in roughly four days through three stages. It then molts into the copepodid stage, becomes a parasite, and attaches to a fish host, typically on the gills.

Over the next seven days, the parasite goes through five different copepodid stages. The copepodid stages can also be found on the gills but are not embedded in the tissue.

In the final copepodid stage, the male detaches, but the female remains in this stage until it reproduces and dies.

The entire life cycle may take between 18 and 25 days at about 25 to 30 degrees.

Signs & Symptoms of Anchor Worms on Goldfish

Goldfish Anchor Worm

-Intense inflammation and hemorrhage may commonly occur in the attachment site, making the area appear red and somewhat painful.

-These inflammatory lesions increase the risk of secondary bacterial infections that may eventually cause death or serious health complications.

-L. cyprinacea parasitic females commonly appeared as a small, gray-greenish parasite attached at focal points along the sides of a worm on the base of the flanks, to the edge of the operculum, on the base of the flanks, dorsal and tail fins.

-Redness, ulceration, or small white-green or red lesions (appears like a red welt) in the skin of affected fish. Host fish also shows clamped fin and fin rot.

Treatment for Anchor Worm in Goldfish

-Both organophosphates and potassium permanganate are the most common Anchor worm treatment used to control L. cyprinacea. Potassium permanganate is an effective method of eliminating worm eggs and larvae for aquarium fish.

-Add three tablespoons of aquarium salt per gallon of water. Salt helps to reduce the osmotic imbalance of fish.

-Antibiotics such as Oxytetracycline and Tetracycline can be used for secondary bacterial infections.

-Malachite green, formalin dip, and organophosphate insecticides (trichlorfon) were used to prevent the lernaeid life cycle from remaining in the tank.

-Copper sulfate and Methylene blue may be used to disinfect the fish tank and the wounded region.

Prevention of Goldfish Anchor Worm

When it comes to preventing Goldfish anchor worm, it is important to keep your fish healthy and parasite free. Here are a few tips to help:

Protect Rote of Transmission

Protect rote of transmission to avoid the introduction of parasites into the aquarium tank. Keep your tank clean and clear of debris.

Quarantine and Screening

It is highly advisable to practice quarantine measures and screening of potential infestations to prevent the introduction of parasites.

Infected fish need to be separated from the main tank and placed into the quarantine tank.

Reducing Stocking Density

Always avoid high stocking density and overfeeding. Monitor the water temperature and provide cool water when necessary.

Proper Diet

Maintaining optimum feeding regimes helps prevent malnutrition and increases the immunity of fish.

Do not overfeed your fish. Never give your fish any live food that may contain maggots or other parasite eggs.

Water Change

Aquarium water may be replaced by clean and fresh water. Partial water exchange is vital for maintaining. The key to preventing anchor worms in Goldfish is to keep their environment clean and free of debris.

To do this, regularly vacuum their aquarium and clean the filter. Test your water for pH levels regularly and make any necessary adjustments.

Proper Water Quality.

Pond dying and soil and water treatment by bleaching powder or chlorine treatment was experimentally observed for best results in preventing anchor worms.

If your fish has an open wound, make sure to disinfect it with a weak bleach solution before covering it with a bandage or giving them antibiotics.


Can humans get anchor worms from fish?

Anchor worms are parasites that live in the skin and gills of fish. Humans cannot get them from eating fish.

No, humans cannot get anchor worms from fish. Anchor worms are a type of parasite that can only be transmitted between different species of fish.

How long can anchor worms live without a host?

Anchor worm can live approximate 10 days without a host.

Final Words

In conclusion, it is evident that the anchor worm can be a major problem for goldfish. Not only can they cause physical damage, but they can also lead to other diseases.

If you notice any signs of an anchor worm infestation, take action immediately. There are a few different ways to get rid of them.