(Spironucleus sp.)

Common Indicators: Ulcers on head and along midline, emaciation,  stringy white feces, pale color

The term “Hexamitasis” covers disorders caused by a range of flaggellate protozoan parasites in both marine and freshwater environments. Because it can cause lesions on the head, it is sometimes referred to as ‘hole in the head’ — but is distinct from the nutritional disorder that can often share this descriptive. However, due to it’s nature, Hexamitasis can have the effect of inducing nutritional deficiency in fish, contributing to the symptoms of the  nutritionally-related disorder as well such as becoming thin and wasted.

Studies have suggested the disorder is caused primarily (if not exclusively) by parasites in the various Spironucleus species.

Hexamitasis infections can also be associated with other secondary infections or parasites due to the reduced resistance of the fish so infected. It is generally recognized  that poor water conditions, insufficient filtration, stress due to overcrowding, etc. provide an opportunity to these bacteria, as water polluted with organics, ammonia and nitrates  provides a rich nutrient culture for them and induces stress on the fish, reducing their resistance. In addition, common hypothesis is that poor diet can leave fish susceptible to Hexamitasis due to a weakened immune system.

New Life Spectrum® nutrition formula provides complete nutrition that will generally support fish health and a strong immune system, when combined with good water conditions. However, this alone may not be enough to prevent Hexamitasis.

In these cases, where Hexamitasis is properly diagnosed, New Life Spectrum® HexSHIELD pellets can attack the parasite infesting the fish. HexSHIELD powder water treatment bath solution can be used in cases where the fish are not eating or responsive to food, as well as in early stages.


Bibliography & Further Reading

Noga, Edward J. “Fish Disease Diagnosis and Treatment.” 2nd Ed. John Wiley & Sons; 2010

Fenner, Robert. “The Conscientious Marine Aquarist.” TFH Publications; 2001

Bassleer, Gerald. “Diseases in Marine Aquarium Fish.” Bassleer Biofish; 1996


Monks, Neale. “Hexamita – Fish Hole in the Head Disease: Identification and treatment of Hexamita or fish hole in the head disease.”  FishChannel.com (Aquarium USA Magazine); http://www.fishchannel.com/fish-health/freshwater-conditions/hexamita.aspx

Advisory: The information contained in this article entry is for informational purposes only, and is not a substitute for consultation with a veterinary professional nor treatment under the supervision of a veterinary professional. New Life International does not guarantee the accuracy or completeness of the information nor of the sources cited as reference. This articles is not a diagnostic tool or reference, nor should be considered treatment advice by New Life International.

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