Ive used and sold this product wholesale. Its distributed by Eheim to north america or at least that was the case a year or two ago. Good product for preventative use imo. It ran its course very quickly meaning it didn't gain much popularity.
I picked some up, gonna see how it works out. Never had any major issues (knock on wood), but have had some minor outbreaks. Better to be safe than sorry if you have a fair sized investment...