I used 2 grams (ground up into fine powder, so it will dissolve) for 60 gallons of water.
That was just a guesstimate. I've been looking online, and one person stated they used "one-eighth of a teaspoon" for 50 gallons, but that is much less than what I used. I wish I could give you a more exact dosage for them.
Most of my fish did fine with 2 grams per 60 gallons, even the bristlenose plecos and yoyo loaches. The only one that seems to be having problems is my angelfish, but he was showing stress before the treatments, and it could be completely unrelated.
