1. Anchor Worm - Red swelling appears around the affected scales. If looked at closely the tail of the anchor worm can be seen. With careful pulling on the tail, the worm can be removed and an anchor shaped head will emerge from under the scale. If the anchor worms are not treated quickly, they will multiply and sometimes more than fifty can attach to the body. It makes the Koi weak and eventually it will die.

The best treatment of anchor worms is to use Dipterex or Dylox as an additive to the pond. Another chemical used is called "Demilin" (Japanese name) and this destroys insects. Check with your medication supplier.

2. Fish Lice (Argulus Foliaceus) - Fish lice are about 5 millimeters (3/16") in size. They stick to the body of a Koi and Sap its strength. If left too long, lice can enter the body and cause a secondary infection, such as "hole in side", by providing an open wound.

Treatment for fish lice is the same as that for anchor worms. Because these parasites cause secondary infection, ponds should also be treated with Methylene Blue or Malchite Green.

NOTE: DO NOT OVERDOSE WITH ANY OF THESE MEDICATIONS FOR FISH LICE OR ANCHOR WORM AS IRREPARABLE DAMAGE CAN BE INFLICTED ON THE KOI.

*Information on this page is an excerpt from "KOI" by Grant Fujita, available at the AKCA online bookstore.