Just wanted to share my experience with this. I have found it to be an effective quarantine medication. I have treated wrasse's, damsel's and recently a pair of black capped basslets. Plus sides are, it is gentle on the fish and it treats ich, velvet and flukes, as well as some bacterial infections. The only down side for me is that it has to be added daily. I have a molly that went through it's initial treatment as well as 3 others, with no obvious side effects.