Anchor worms are crustaceans and are parasites that infect the fishes. Once they infect the fishes the fishes are prone to other diseases which cause the death of the fish. It is actually not the anchor worms that cause the death of the fish but the other diseases that affects the fish after it is infected by the anchor worms. The risks of the fish to attract other infections are high after it is affected by the anchor worms.
Anchor worms can swim freely before they get into the fishes. Once they get into the fishes they get so deep into them that it is difficult to bring them out without affecting the fishes. The life of anchor worm starts once they get into the fishes. Anchor worms get into the muscles and start living there for months together and progress through the different stages of their life cycle. When they leave the infected fish ugly wounds are formed in the fish. These wounds caused by anchor worms give way for other infections which might be deadly for the fish. Once they are out of the fish they release other eggs and the life cycle starts for the new worms.
The anchor worms live for a very long period in the fish and hence it is not easy to locate where and how they got infected with anchor worms. You can suspect the infections by anchor worms once the fish starts rubbing themselves on the sides of the aquarium or any object that is present in the aquarium. This is one of the symptoms of infections of anchor worms. However the same symptoms are also found for some other infections too. One of the other symptoms you can see is white green threads hanging from the infected areas of the fish. The infected area will be red in color. Apart from that fish will have difficulty in breathing. It is common to find infections at the base of the fins. With such symptoms you can suspect anchor worm infections.
Potassium permanganate is used in the treatment of fish that is affected by anchor worm. The infected fish is given a bath with a mix of water and potassium permanganate. 10 mg of potassium permanganate is mixed with one litre of water. Bathing for 20 to 30 minutes is needed to treat such a fish. It is also a good idea to treat the entire aquarium of fishes with potassium permanganate. If you decide so you can mix 2 mg of potassium permanganate per litre of water in the aquarium to prevent infections to the other fishes. The color of the water will change in the aquarium when you mix potassium permanganate. Giving the fish a dip in salt water is also a treatment done. Dips in water with formalin for about 30 minutes are also done as a treatment. In this mixture about 3 ml of formalin in 2.5 gallons of water is used. To prevent other infections of the fish you can add about 2 tablespoons of salt to the aquarium. If you can see the anchor worm you can also remove it using tweezers.