Chilodonella a common parasite, often occurring at low temperatures. It is a threat as it often causes severe damage before any signs are evident. Costia is able to reproduce rapidly under ideal conditions and cause serious tissue damage, particularly in the gills. Fin rot With few exceptions, fin rot is always precipitated by stress and is often one of the first signs that a health problem exists. Skin and gill flukes are common parasites that are often the precursor to gill damage, bacterial infections and ulcers.
Treatment can sometimes be tricky.
Fungus Saprolegnia infections can spread rapidly and even though the damage is often superficial, prompt treatment is essential to avoid fatalities. Parasites - an overview Fish are potential hosts to a range of parasites. Trichodina a common parasite. At low levels it doesn't pose a health problem. However, as with most parasites they have tremendous reproductive potential.