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Keeping goldfish isn’t always the most glamorous job. You have to manage the tank properly, and few tasks will make you feel less glamorous than being covered in dirty water while your goldfish beg for food! However, what’s worse is dealing with parasites on your goldfish for the first time. They can be unsettling for you but uncomfortable and even deadly for your goldfish. Keep reading for more information on goldfish lice and anchor worms.
What Are Goldfish Lice?
Goldfish lice are crustaceans known as copepods, and they go by the scientific name of Argulus trilineatus. They measure approximately 3–4 mm when fully grown and are translucent, which can make them difficult to spot in your tank or on your fish. Males tend to be slightly smaller than females.
Fish lice use a needle-like mouthpart to suck blood from fish, much like a mosquito. If you look closely at fish lice, you will see that they are usually round and almost alien in appearance. These parasites are highly contagious and can rapidly spread throughout an entire tank if they are not caught and treated early enough.
What Are Anchor Worms?
Like fish lice, anchor worms are copepod crustaceans. They go by the scientific name of Lernaea cyprinacea and are easier to spot than fish lice. Anchor worms attach to a fish via their mouthparts while their bodies jut out from the fish’s body. Anchor worms are ribbon-like and pretty recognizable as parasites when you spot them.
Anchor worms are highly contagious and will quickly infest your whole tank. They can create lesions on your goldfish’s skin, leading to scale loss. They are frequently spotted in and around the gills and gill covers. Sometimes, they aren’t particularly noticeable until you see them moving as your fish’s gills open and close with respiration.
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What Are the Signs of Fish Lice and Anchor Worms?
Fish lice are visible on goldfish, though they can be difficult to see. They usually appear as small, greenish dots or flecks across the body of your goldfish. Anchor worms appear as small, white, ribbon-like worms that hang out from the fish’s body, usually sticking out from between scales.
Goldfish with fish lice or anchor worms often exhibit flashing, a behavior that involves rapidly darting around the tank and attempting to rub up against items within the tank. Flashing indicates itching or discomfort and is usually done to eliminate this sensation. Other signs may include fin clamping, rapid breathing, pale coloration of the gills, lethargy, and inappetence.
How Can I Treat Goldfish Lice and Anchor Worm?
If left untreated, fish lice and anchor worms can lead to severe anemia, secondary infections, and death. Both parasites will reproduce and spread in your tank until they are treated. The most effective treatment for fish lice is medications with cyromazine as the active ingredient. Cyromazine is an antiparasitic that limits the parasite’s ability to produce and maintain its exoskeleton.
Without an exoskeleton, the fish lice will die. While cyromazine is a highly effective treatment for fish lice and anchor worms, it is unlikely to kill all the parasites in a few days due to its mechanism of action.
If you’ve treated your fish with cyromazine and still see indications of an active infestation, you may need to continue or repeat the treatment. Make sure to follow the instructions for the product you are using carefully. Since this is an antiparasitic medication, an overdose can kill your goldfish and anything else in the tank with it.
How Can I Prevent Goldfish Lice and Anchor Worms?
Due to the contagious nature of both these pests, the best treatment is prevention. They can weasel their way into your tank via new fish, plants, or infested water, like if you were to introduce a fish from the local pet store directly into your tank. The best prevention for parasites is initiating a quarantine protocol for new fish and plants before introducing them to your tank.
Plants can be quarantined or given a bleach or hydrogen peroxide dip, but new fish and other animals should be quarantined in a separate tank for 2 weeks at a minimum. Ideally, a fish’s quarantine should last 4 to 8 weeks to ensure you’ve had ample time to monitor for signs of parasites and other illnesses.
Maintaining good water quality can prevent and treat fish lice and anchor worms. Routine water changes can remove eggs and free-swimming parasites in the water column. This can be especially important if you treat a pond or tank you intend to allow to overwinter in cold temperatures. At the end of the season, it’s a good idea to thoroughly clean the pond or tank to avoid having a full-blown infestation on your hands once the warm temperatures roll back around.
Final Thoughts
Fish lice and anchor worms are creepy and unsettling creatures to spot in your tank, but they can be treated. Preventing the parasites from infesting the aquarium is your best chance of keeping your tank safe and protecting your fish. However, sometimes, this isn’t possible, in which case early identification and treatment give your fish the best shot at survival with few complications.
It’s good practice to visually inspect your fish at least a couple of times per week to ensure that you don’t see any evidence of parasites on the skin, scales, gills, or fins. Catching parasites early will make treating them so much easier!
Related read:
- How to Get Rid of Camallanus Worms in Fish
- Have Detritus Worms in Your Aquarium? Here’s How to Get Rid of Them
- Goldfish Diseases
Featured Image Credit : NatureDiver, Shutterstock
