Praziquantel does nothing to thread/ round worms like Camallanus.I used praziquantel on my 55 and the 29, I think, earlier this year, although I am not entirely sure why, it was a very long and busy spring, I think I need to check my calendar. I gather that it does not treat camallanus worms? I have not treated the quarantine tanks with prazi or anything else in the way of a wormer. But the fish have done well and nothing visible hanging out of their anus, nor any bloating, or stringy poop