Aquarium Parasite Treatments
Aquarium parasitic medications treat parasitic infection, the most common of which is ich (white spot disease), a protozoa that afflicts marine and freshwater fish. Common parasites include lice, hole in head, velvet, flukes, worms and black spot. You may observe irritated behavior from your fishes (e.g. rubbing against things) before visible signs of infection. A little aquarium salt is an effective treatment against some freshwater parasites, especially Costia.
Do not use copper treatments in reef tanks, with invertebrates or live plants. Monitor copper levels to make sure they don't get too high, and remove it with carbon after treatment.