Supaverm is easy to find.

What It Is:
SupaVerm© is a white liquid. It's a suspension of Closantel and Mebendazole imported from Europe for use as a drench dewormer for sheep.

What It's Good At:
Applied to the water of ornamental Koi, SupaVerm© eliminates fluke (trematode) infestations within 3 days.

Background:
SupaVerm has been extensively tested and reviewed at KoiVet.com. We suggest you take the time to visit there and familiarize yourself with the concepts. Nothing yet has been found to be as simple as this product. Most people are dosing this at one milliliter (1 cc) per 100 US gallons, once. Many others will apply a second dose 3 days later to ensure complete eradication of all forms of flukes.

Pros:
SupaVerm© has been shown to be safe in single and double applications to eliminate Flukes without negative effect on Koi, plants, or the beneficial nitrogen-reducing bacteria in the filter. No water changes are indicated.

Cons:
THIS PRODUCT WILL KILL 100% OF TREATED GOLDFISH DEAD! IT IS NOT FOR GOLDFISH. IT IS FOR KOI.

There are other species of fish which are sensitive to SupaVerm© as well. Use in any other species of fish than ornamental Koi is sheer lunacy.

Dose: Variable, based on experience and preference and whether the Supaverm is diluted. Normally: One milliliter of pure, per one hundred US gallons, applied on Day One and Day Two.
Supaverm is easy to find.