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Uronema marinum is a saltwater parasite that can prove fatal for marine fish. The parasites behind the disease are ciliated protozoa that live freely in marine environments. This disease will as most other diseases only infect already weakened fish and the best way to prevent this disease is therefore to keep a clean aquarium with healthy and well fed fish and avoid overcrowding. You should also make sure to keep new fish in a quarantine tank where you nurture them into good health before letting them into your general population. Uronema marinum usually feeds on bacteria but will attack weak fish as well, eating at its internal organs and muscles. Uronema marinum is often misdiagnosed as it shares symptoms with a number of other bacterial and parasitical diseases. It is however important to diagnose the disease correctly as it is fatal for many types of marine fish. The symptoms of Uronema marinum includes rapid breathing, flashing and loss of color (the fish becomes pale) as well as weight loss and dehydration.
Fortunately there are several ways to treat this disease. One way is to bath your fish in a freshwater tank for 2-3 minutes (until the fish show signs of stress but no more than 3 min). A variety of this treatment is to place the fish in a hospital tank with low salinity (1.011) for 21 days. This treatment should not be used with sensitive species. Another method is to use chemical treatments such as Methylene blue, Copper Sulfate or Malachite green. Always follow instructions provided with the product you purchased if you choose to use a chemical treatment. There are also other medications such as the antibiotic Nitrofurazone that will help treat Uronema marinum.
