Anemia is not very common in fishes. When it does occur, however, the veterinarian will seek to treat the underlying cause of the condition. For example, increasing folic acid in the fish's diet can resolve anemia do to a deficiency in the substance. Anemia due to infections and parasitic infestation, on the other hand, are treated with medications for the infection, followed by a thorough cleaning of the fish's environment (i.e., aquarium, pond). If necessary, the infected fish may be quarantined until all traces of the leeches and its larvae and eggs are gone. Water should also be tested regularly to keep nitrite levels correct.
A condition of the blood in which normal red blood cell counts or hemoglobin are lacking.