Skip to main content

Koi Parasites

Maintaining good water quality is your first step in preventing parasite outbreaks.
When Koi are weak from stress parasites are encouraged to multiply. 

Select a parasite topic from above. Review this helpful information to become more familiar with pesty Koi parasites. 


Your koi pond and its inhabitants may be harboring and/or cycling parasites at this very minute.  Parasites don't take a break; some are prevalent in warm water, while others make an appearance when the water temperature is low. Koi can contract both internal and external parasites. 


Gain the confidence to diagnose and treat Koi parasites.
Learn how to treat and defeat them effectively.
Generally, all ponds have parasites. Even healthy fish can host parasites. 
Healthy fish can live with a small number of parasites for years. However, if your fish become extremely stressed or sick the parasites will gain an edge and flourish. That can lead to serious complications, up to and including the death of your pets.   


Obvious signs of a parasite infestation:

Fish rubbing on the pond bottom or edges
Hanging under waterfalls
Lack of feeding 
Lying on the pond bottom
Sores, lesions or ulcers
Loss of weight

Unfortunately, most Koi parasites are microscopic, although adult Anchor Worms and Fish Lice are visible to the unaided eye. You may become suspicious of their presence long before seeing an adult parasite. Keeping a journal of fish activity will be a great resourse  when the time for action arrives. 


* Secondary infections are common occurances following parasite infestations. 


Want to learn more? 




Customer Reviews