Chilodonella

As with many parasitc infections Chilodonella can lay doormant for prolonged periods of time, being an opportunist to take hold if your fish become stressed. It has the same life cycle as Costia, and can be treated with Malachite Green and Formalin. Salt is also known to be effective. This parasite affects the gills and skin resulting in tissue damage which can lead to secondary infections.  The reproduction rate can be rapid, Chilodonella is a lethal parasite and mortality is to be expected.  In fact it is sometimes the death of a fish that leads to this parasite being diagnosed.  It is one to watch out for, especially at spring time.