Saltwater Fish and Parasites

Parasites can cause infection or death in saltwater fish.

There are many different parasites that can affect saltwater fish in their natural habitat. These parasites can also infect domestic aquarium saltwater fish. They can cause a wide range of symptoms ranging from skin and scale irritation to death in fish populations. The symptoms of infection can vary depending on the type of parasite.

Types

There are five common types of saltwater fish parasites. Amyloodinium is also commonly known as "velvet." The University of Florida IFAS Extension indicates that this disease is caused by a parasite called Amyloodinium ocellatum that infects the skin and gills of saltwater fish.

Cryptocaryon irritans is also called "white spot" because white spots form on the fish's body. This type of ich (pronounced ick) can be caused by poor water quality, according to the Fish Vet website.

Brooklynella is a protozoan that can infect fish if there are high ammonia or nitrate levels in their water.

Diplopstomiasis is also known as "black ich." It is caused by the larvae of a parasitic flatworm called turbellarian. The Seymour Aquariums website indicates that this disease affects mainly angelfish and yellow tangs.

Uronema marinum is a ciliated protozoa, according to the Aquatic Community website. The parasite usually eats the bacteria in saltwater tanks, but in dirty or overcrowded tanks, Uronema will attack weak fish.

Effects

Symptoms of parasitic infection vary depending upon the type of infection. The early symptoms of an Amyloodinium outbreak are a loss of appetite, scale loss, and mucus growth. Their fins and scales may also develop a brownish or gold luster. Cryptocaryon irritans causes lethargy in fish, and they may try to rub up against objects. As the disease progresses, white spots will multiply on the fish, its eyes will become cloudy, and hemorrhaging may occur. The Fish Vet website says brooklynella may cause a fish to lose its appetite and impair its gills. As the infection progresses the skin may start to deteriorate. Diplopstomias is characterized by black spots that cover the body while uronema causes weight loss, color loss and rapid breathing.

Treatment

There are a number of different treatment options that can be used to treat infected fish. Amyloodinum and brooklynella can be treated using copper. Medicated freshwater dips can help control uronema and cryptocaryon. Diplopstomiasis can be treated with a chemical called formalin.

Prevention/Solution

Fish Vet indicates that many parasitic infections can be avoided if the tank is kept clean. The water must be of high quality and all debris should be filtered out to avoid contamination. The best way to avoid parasitic infections is to quarantine a new fish for a minimum of three weeks before introducing it to an existing aquarium population.

Warning

The copper treatments used to treat amyloodinium and cryptocaryon can be deadly to invertebrates. To avoid having to completely restock your reef tank, Fish Vet suggests catching the fish and giving them the copper treatment in a separate tank.

References

• University of Florida IFAS Extension: Amyloodinium Infections of Marine Fish
• Fish Vet: Cryptocaryon
• Fish Vet: Brooklynella
• Seymour Aquariums: Parasitic Diseases: Diplopstomiasis
• Aquatic Community: Uronema Marinum