Hexamita is a disease that is caused by protozoa that is categorized as an intestinal flagellate. You might have heard about skin flagellates that attach to the skin of the host. But Hexamita is caused by intestinal flagellates. This means that the protozoa attaches to the intestines and infects the digestive system of the fish. Only a certain species of fishes are mostly affected by Hexamita. These species include Discus, Oscar, and Cichlids. The Hexamita disease is often confused with the hole in the head disease which is Head and Lateral Line Erosion 'HLLE' disease because these two infect the fish at the same time mostly.

If you see the faeces of the fish in white color or slimy then the fish might be affected by Hexamita. At this stage the fish will be healthy and it is difficult to say that it is infected. Food intake will also be as usual. As the disease progresses, you will see the symptoms that are similar to the symptoms of the hole in the head disease. That is why many get confused with this disease. The fish will become darker as the Hexamita disease progresses. Sometimes the fish would even become black. If you see the head of the fish it will be thin at this stage. Regarding the movements of the fish you might see it swimming backwards. The head of the fish will face downwards when it is infected with Hexamita and is in the advanced stage. Since the infections affect the digestive tract the nutrients in it are taken by the protozoa and the fish gets little nutrients. This leads to weight loss in the fish. You can even see the fish hiding in the corners or other places and even while hiding the head of the fish will face downwards. Since there is deficiency in the nutrition this could well be the reason for the hold in the head disease too which also affects the fish in this stage.

Internal medication is the only effective option for the treatment of Hexamita as the disease itself affects internally. Mixing the medication in the fish food is the best way to treat Hexamita. Mix metronidazole at one percent to the fish food and feed the fish. For example, if you have 100 mg of metronidazole, you can mix it to 10 grams of fish food. Since you are mixing the medication with the fish food you have to make sure that the medicated food is eaten by the fish. For this you have to limit you regular food to certain extent and then add the medication food to the aquarium. For more effective treatment you can also mix metronidazole in the water in the aquarium. The level of the medication to mix in aquarium water is 12 mg per litre of water. Treating the water in this way for three days makes the treatment effective against Hexamita.