I have posted this information on 2-amino-5-nitrothiazole earlier in this forum but I can repeat it again.
Very successfull breeders of Parosphromenus and Betta species in Germany found out (about six years or more ago) that a medicine sold here to combat hole disease with Discus worked perfectly in erasing Oodinium. The medicine is called “Hexa-Ex”, it is manufactured by the big company “Tetra” and sold as tablet. Shortly after Tetra another company, JBL, sold the same medicine with the name “Spirohexol”.
And the point is: Both products consist of only one ingredient: 2-amino-5-nitrothiazole.
Since that time all of us only use this medicine to combat Oodinium. All other methods have proved to be not as effective than this.
Many of us have tried to get this chemical substance free as a powder. This is difficult, for it is sold only to veterinarians. I do not know why.
When Jacob mentioned a problem with Oodinium, I suggested to him trying to get hold of Hexa-Ex (Tetra) or Spirohexol (JBL) or the substance directly. But he replied that he could not find it.
I only can repeat our experience: It’s the best medicine against that disease. There is no problem with dosage. We have never experienced any secondary effects.
Certainly, it’s a strong chemical means. We all prefer more natural methods or lighter chemical means. But there have been severe losses of valuable fish (self-caught, few specimen, the last of a form) by that lighter methods. Since that time we use 2-amino-5-nitrothiazole if things mus be combatted successfully. (By the way: The substance must be stored very cool, best in a refrigerator. Otherwise the yellow will turn into a brown and the stuff will become worthless).