Lernaea which is known as anchor worm exists as an ectoparasite that infects both ornamental and farmed freshwater fish species. The females attach themselves to skin and fins and gills to suck blood and tissue which leads to skin discomfort open wounds, stress, diminished growth and secondary infections. The organism produces free-swimming larvae which find hosts while its stationary females generate eggs during the entire time which results in fast population growth. The infestations appear as thread-like formations which makes them easy to identify. Management practices need to combine chemical applications with physical removal methods and water quality enhancement and fish welfare improvement.