As much as I hate Jungle products it seems like a lot of people recommend Jungle Parasite Cure.
Try using the technique here - http://www.monsterfishkeepers.com/forums/showthread.php?339362-Treating-Hexamita-aka-Spironucleus
API General Cure is something worth trying as well. If you soak the food in prazipro I would think you would need to soak it in garlic extract as well, must taste awful.
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