I had camallanus worms that came in with an infected celebes rainbow and spread to the rest of my fish. They really suck. Prazipro won't work, but I was able to get rid of them using fenbendazole. You can buy it at petsmart in the dog section. It's sold as safe-guard and is used as a dog dewormer. It does not mix with water well, so soaking the fish food in it won't work (I tried). I ended up mixing it with unflavored gelatin and pellet food that I'd ground up in my coffee grinder. After it had solidified, I cut it into tiny pieces and the fish gobbled it up. Fed it that way for around a week and it took care of the adult worms. You do have to retreat after 3 weeks (I think) to take care of the eggs that have reinfected the fish. I did treat the tank with the prazipro in that time, just in case it was able to help with the eggs. Don't know if it helped at all, but I had it on hand and figured it couldn't hurt.