Hexamita is a flagellate protozoa that affects the gastrointestinal tract of ornamental fish. Protozoa are microscopic, single-celled organisms that may or may not be parasitic to fish. 

Can Fish Die from Hexamita?

Even though Hexamita is progressed slowly, it is often associated with high mortality if left untreated. Hexamita causes severe intestinal disorders in fish.  It’s believed that some Hexamita species are resistant to common medication such as Metronidazole which makes it hard to treat.

Hexamita in Tropical Fish and Aquarium environments
Hexamita in Tropical Fish and Aquarium environments

Causes of Hexamita in Tropical Fish

It is real hard to imagine a live aquatic ecosystem without any parasites! All living organisms, including fish, can have parasites including protozoa and parasitic worms. In other words, parasites are a natural components of all healthy aquatic ecosystems. Hexamita mainly targets Dicsus fish with weakened immune system. That’s why only some fish catch hexamita apparently from nowhere.

Discus fish is very susceptible to Hexamita
Discus fish is very susceptible to Hexamita

Some Facts about Hexamita

  • Because of the facts that Both Hexamita and Spironucleus are one-celled protoza that can cause changes in fish poop shape & color and also the same treatment may be applied to both, Spironucleus species is sometimes incorrectly identified as Hexamita.
  • Most of the time, the Spironucleus is responsible for hole in the head disease in fish, whereas Hexamita is known to cause severe intestinal problems.
  • Most Hexamita species are non-parasitic organisms!
  • Not all white feces in fish is a result of Hexamita! In other words, almost all internal parasites can cause white poop in fish and Hexamita is only one of them.
  • Although almost all fish in the affected tank carry the parasite, because of the reasons mentioned earlier, not all of them will get sick.

Hexamita Symptoms in Fish

Hexamita may not causes any specific clinical signs and symptoms in fish.

Treatment for Hexamita in Fish

Don’t use any kind of medications as long as fish still eat! Try commercial medicated foods like New Life Spectrum Hex Shield or medicated beef heart if there is still some appetite in fish! As Hexamita is a well-known problem among tropical fish including Discus, there are a variety of treatments for Hexamita in fish.

Metronidazole (Flagyl)

Metronidazole shown to be an effective treatment for Hexamita in tropical fish; Pure Metronidazole powder administered in a medicated food is the most effective method of treating Hexamita in fish. However, if discus fish stop eating, bath treatment is alternative method. Resistance to Metronidazole, as well as bad water solubility, makes this drug a little bit hard to manage by newbies.

API General Cure™

API General Cure™ Powder is a great medication, if not best, that treats Hexamita in tropical fish. API General Cure™ Powder can be purchased from all Pet Shops in the U.S.

Seachem MetroPlex™

MetroPlex™ is an effective treatment for Hexamita in discus and tropical fish.

Thomas Labs Fish Zole™

Thomas Labs Fish Zole™ from Thomas Labs is a another medication that is effective against hexamita.