What is Fish Lice?

Fish lice are parasites in fish, often attaching to the skin and gills of fish with hooks and spines on their bodies. Lice damage the skin, suck blood, inject toxins into the body of Koi fish, causing inflammation, bleeding and potentially bacterial infection.

Specific symptoms:

Koi fish with fish lice often have physical and behavioral signs. Some fish may not have any external signs of infection, but you may notice the following signs:

• Itching: Koi with lice often glance at themselves, rub themselves against the walls of tanks, bottoms or objects in the lake, or jump to the surface of the water to relieve itching.

• Dots on fish: Usually, small red dots will appear at the site of the louse infection. Red dots are the result of small, inflammatory hemorrhages caused by fish lice puncturing fish flesh.

• Damaged skin: The area of skin attacked by lice will have scratches, inflammations and may appear sores.

• Loss of oily layer: Fish lice suck blood from the host fish, causing the loss of the protective oily layer on the Koi's skin, causing the skin to become dry and wrinkled.

• Weakened health: Fish lice cause stress and stress to koi, leading to weakened health, reduced physical condition, increased risk of other diseases.

• Decreased reproductive performance: Fish lice affect the reproductive process of koi, reducing their ability to lay eggs and the number of fry born.

• Lethargy: Due to lice infestation, your fish may become lethargic and swim less than usual. This happens due to blood pressure caused by lice. Blood loss due to parasites can lead to coma.

• Unusual swimming: Fish with lice may swim abnormally due to feeling discomfort or trying to shake the lice out of their body.

In some cases, there may be no obvious signs of the disease other than the presence of parasites. Lice can be easily seen in the adult and later stages with the naked eye when the fish are swimming in the water.

Causes of fish lice:

Koi fish can get lice due to a variety of causes, including:

• Bad environment: The koi fish farming environment is not clean enough, and the temperature and water quality are not controlled, which can facilitate the growth of fish lice.
• Poor immune system: Koi fish that are weak, have a poor immune system or are stressed are more likely to suffer from fish lice.
• Contactwith louse-infested fish: If koi come into contact with fish contaminated with lice or the culture environment contains louse-infested agents, it can lead to the spread of disease.
• Lack of nutrition: Koi fish that lack nutrition and don't eat enough of the nutrients needed to maintain a strong immune system can also be susceptible to fish lice.

How to treat Koi fish lice:

For a thorough treatment of this disease , it is first necessary to carefully examine each animal in the aquarium . Fish infected with lice should be separated . Next, the following methods can be used:

•    Use of propolis:

First , you need to remove all the lice on the carp's body with medical tweezers . Next , spray propolis on the bite of the lice to prevent infection . Propolis is likened to a natural antibiotic that effectively prevents infection .

•    Use of bath pills:

Specialized bath drugs can be used to kill lice. The bath medicine can be diluted in water and the koi fish are soaked in this solution for a certain period of time. Dimilin is an effective Koi fish lice remedy. The use must be absolutely in accordance with the instructions recommended by the supplier.

•    Use of antiseptics

In addition , you can also use salt water and apply antiseptic to the skin of the fish, which is also very effective

Some notes in the process of treating lice for Koi fish:

•    Farming environment control:

Make sure that the koi fish farming environment is always clean and control the temperature and water quality. A good farming environment will help koi fish have a strong immune system and resist the growth of lice.

•    Nutritional Support:

Provide balanced nutrition for koi fish to strengthen the immune system and help the fish be healthier in fighting the growth of lice.

•    Perform treatment according to the expert's instructions:

The use of drugs for lice should be carried out according to the instructions of a specialist and adhere to the correct dosage. Improper use of the drug can harm koi fish and the farming environment.

When catching fish for healing must be very careful , avoiding fish panic , stress . Being infested with lice can make fish very uncomfortable and susceptible to stress if not cared for properly. 

Note that preventing lice is more important than treatment. Therefore, follow the rules of hygiene and control of the culture environment to avoid the spread of lice in the koi aquarium.

Anti-lice in Koi fish:

Prevention is better than cure. Even if your fish are completely healthy, you should take necessary measures to prevent water lice in fish.

• Standard aquarium quality: the aquarium meets the standard when the ideal pH in the water is about 7 – 7.5, the filtration equipment ensures clean and safe water purification, the temperature in the aquarium is from 20 to 27 degrees Celsius, ideally 25 degrees Celsius.
• Check regularly: Check the skin of koi fish regularly to detect the appearance of lice early. If you see any symptoms such as loss of scabs or redness, check carefully.
• When buying new fish, it is necessary to take a bath to disinfect with potassium permanganate, observe the fish in the tank, if you do not see any abnormal symptoms, then release them into a large aquarium.
• Buy fish from reputable and quality establishments to avoid buying sick fish
• Design and construction of aquariums to ensure good quality and meet technical requirements.
• Strengthens the immune system: A strong immune system will help koi fish fight the effects of lice. You can provide koi fish with a balanced diet and add nutrient-rich foods such as garlic or vitamin C.

Above are some immediately effective ways to treat koi fish with water lice as well as how to prevent koi fish from being attacked by water lice. Koi fish with lice is one of the diseases that is not dangerous at all. However, it is also necessary to treat quickly and thoroughly to avoid affecting the health and influence of fish. If you need more information, contact Quhaku Koi Farm for advice and solutions to the problems you are experiencing. You can also refer to good articles about Koi fish farming experience on our website. Quhaku is always with you!