Treatment of fungal infections is relatively easy. There are a great many commercially available products for this, including MarOxy by Mardel Laboratories and Super Sulfo and Would Control by Aquatronics. This is a very common disorder which infects all kinds of tropical fish. 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.