Fin reduction. Fin retraction is also a common disease in breeding Thai bettas. The diseased fish show darkening of body color and loss of appetite. This disease is mainly caused by the deterioration of the breeding environment and the narrow space, which leads to the infection of bacteria in the whole body of the betta fish.

It is relatively simple to treat this disease, but pay attention to it in time treat. Generally choose the drug for the treatment of bacteria, the effect will be obvious.