HKF Fish Lice & Anchor Worm treatment (AKA Dimilin 25W)powder is by far the best treatment for fish lice and anchor worms in Koi and Goldfish! It can also work great to destroy mosquito and midges that hatch in the pond and filters! I normally treat at a dose rate of one gram of Dimilin per 264 gallons on pond/tank water for four days for Koi & Goldfish. It will destroy all stages of these nasty bugs in four days! This is a 1PPM dose rate. After 4 days do a 25%-50% water change when complete. Usually only one treatment will do the job, but sometimes a second treatment one week later is called for for heavy infestations of lice and anchor worms. Comes with complete dosing and application instructions.
Please note the included directions apply to Koi and Goldfish only. If you are treating other species of fish they may require different dosing and treatment protocols.