sera guide - Healthy pond fish

2.8 Diseases caused by crustaceans Observation Fish jump and swim hectically; flat (louse-like), almost transparent crustaceans sized 4 – 14 mm with two black eyes visible on the skin of the fish; red sting marks on the fish skin. Diagnosis: Fish louse / e.g. Argulus Treatment: page 34 16 2.7 Diseases caused by fish leeches Observation Circular bloody inflamed areas measuring 3 – 8 mm on the skin of the fish; up to 5 cm (2 in.) long (often shorter) worms with suction cups at both ends of the body and a ring pattern; can be found on aquatic plants or on the fish themselves. Diagnosis: Fish leech / Piscicola sp. Treatment: page 33 Fish leech Argulus on a Koi