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8 Common Koi Fish Diseases to Watch Out For

8 Common Diseases in Koi Fish in San Diego, CA

Koi are robust, hardy fish with a well-deserved reputation for rarely getting sick. However, this doesn’t mean they’re immune to bacterial, parasitic, or fungal diseases. The key to successful recovery is recognizing symptoms early and starting the proper treatment as soon as possible. Here are eight common koi diseases as well as their symptoms and treatments.

1. Ichthyophthirius Multifiliis (Ich)

Ich is a protozoan parasite that results in white spots that resemble salt developing on the koi’s body and fins. Other symptoms include clamped fins, cloudy eyes and fins, and scratching. A broad-spectrum disease treatment as well as a pond fish treatment (available at Aquatic Warehouse, where you can purchase all the high-quality koi pond supplies you need) are the recommended ways to combat this common fish disease.

2. Flukes

Flukes are microscopic worms that infect koi. They may infect either the gills or the body of a koi. Gill flukes cause fish to flash, jump, or gasp for air at the surface of the pond. Body flukes create sluggishness, flashing, lesions on the skin that resemble spiderwebs, and reddened and/or clamped fins. Both types of flukes are treated with praziquantel, or better yet, MinnFinn (https://www.aquaticwarehouse.com/medications-and-treatments115/minnfinn-freshwater-fish-and-koi-treatment-), a deworming agent and wide spectrum treatment. Many experts recommend treating your koi for flukes every spring and fall as a precautionary measure.

3. Trichodina

Trichodina is another protozoan parasite that attacks koi. Symptoms include lethargy, sitting at the bottom of the pond, gasping for air or breathing heavily, flashing, and small reddish-hued lesions. Trichodina is addressed with a broad-spectrum disease treatment and a pond fish treatment. Feeding your koi high-quality food through the warm months helps them become less susceptible to trichodina in the cold months. This issue can also be treated with the wide spectrum MinnFinn.

4. Dropsy

Dropsy is caused by a bacterial infection and causes a swollen abdomen and scales that protrude. Treatments include an antibacterial and medicated koi food.

5. Fungus

Fungus in koi often presents itself in white cotton-like patches along the body, fins, and mouth. Sometimes it’s green in color. Fungus needs to be treated with an antifungal fish treatment.

6. Fin Rot

Fin rot is another common disease in koi. Affected fish have tails and fins that appear to have been shredded. Treatments include antibacterials and medicated koi food. It’s highly recommended to quarantine infected fish during treatment.

7. Ulcers

Ulcers are caused by bacteria and are open wounds with red edges along the koi’s body. Treatments include antibacterial injections, dips, topicals, pond-wide antibacterials, and medicated foods.

8. Anchor Worms

Anchor worms are another parasitic infection of koi. They are small white threadlike worms that are visible to the naked eye. Sometimes they appear as white pimple-like bumps along the body of the fish. Infected fish will also scratch themselves, flash, have areas of localized redness, and become lethargic. The treatment for these worms is physical removal of the worms, if possible, and a pond-wide antiparasitic like MinnFinn. https://www.aquaticwarehouse.com/medications-and-treatments115/minnfinn-freshwater-fish-and-koi-treatment-

Although koi are known as strong, sturdy fish, they can sometimes fall prey to certain diseases. Being aware of these common issues and their symptoms is the best way you can make sure you’re able to treat these problems early. The experts at Aquatic Warehouse are dedicated to helping you keep your fish as healthy as possible. Drop by or call one of our friendly professional staff today at 858-467-9297.

Contact Information

  • Address: 5466 Complex Street Suite 204
    San Diego, CA 92123
  • Phone: (858) 467-9297
  • Email: sales@aquaticwarehouse.com
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