Garlic is said to help with internals, I am not sure about external parasites. Prazi is the way to go IMO, I purchased some from a link on Koivet and it did a fabulous job for me. The only real drwback is the quantities that you have to purchase. The minimum I could find was enough for 1000 gallons. It takes very little to get the job done, it had no adverse effect on plants or snails in my tanks, and cleared an issue that had haunted my tanks for close to a year. If you can't find Prazi Pro Pm me, I may be able to help.
On a side note, Praziquantel is sold as a cat and dog dewormer under the name of droncit. Your vet may be able to help you with a small supply of it.
Dosage I used was 1 gram per 100 gallons, it's a bit hard to mix, but you simply add it and wait 7 days before you do a water change. no color, no stain, no visible side effects that I could find.
Am I to understand that you actually dip the fish in a high salt concentration bath for a few sec? Seems pretty stressful for the fish, and what do you do to rid the tank itself? Just wondering, because i'd never of it before.
That's the principal of it. Essentially, Saltwater parasites have difficulty with freshwater, and vice versa. It has been a while since I really read up on it, but if I remember correctly, the rapid change in external verses internal pressure more or less causes certain parasites to explode. This only applies to certain parasites and is very limited in it's usefullness. I do not know if Flukes will succumb to it but rather doubt it considering that fluke tabs have remained popular for a long time and are much harsher than a saltwater dip IME. For the most part This treatment is effective on unprotected external worms of various types. It has no effect on parasites which are encysted, buried in the skin, or have their own defense mechanisms. I researched flukes extensively before treating my tanks, and the general consensus with almost every reputable site was Prazi or Fluke tabs, and fluke tabs are very harsh despite their effectiveness. Prazi was IME a dream to use, and definately killed my flukes once and for all.
Dave
Dave