Fish Louse (Argulus)
The fish louse is a totally free swimming crustacean that attaches itself to the fish in a lot the exact same manner as the anchor worm, and also the treatment is the exact same.
The illness could be recognized as grayish patches, generally round, attached to the skin of the fish, mainly around the belly, gills, and areas near the throat.
An alternative technique of treatment would be to treat the aquarium with potassium permanganate, 1/3 grain to every gallon of water. Repeat as essential every 8 to 10 days. No harm will come to the plants or fish.