It is intensified greatly with fish having damaged fins or cuts and scrapes. It is also much more likely in poor water conditions in which there are unacceptable levels of ammonia or nitrites. Fungal infections are also a sign of bullying by other fish. Fin nippers will damage the fins of other fish making them more susceptible to fungal infections and external bacterial infections such as fin and tail rot. Small white pimples concentrated mainly on the fins.
Pimples look like granules of salt.
Treatment of Ich can be difficult. There are several medications and preventatives available including Super Ich by Aquatronics and Maracyn and Maracyn-Two by Mardel Laboratories. This is the most widespread and common freshwater fish disease. The small pustules are actually sacks of tiny protazoans. In a few days, the sacks break open and the parasites fall into the aquarium gravel where they multiply in great numbers.