sorry to read about the sargassum and venustus. both are very nice looking fish.
the only thing i can suggest is to QT fish, especially angels. i do 2 treatments of prazi pro with every fish i get. angels are notorious for carrying flukes and worms.
Yeah I know and understand the risks of not QTing.... but honestly I do not think QT would have saved either fish, and I dont feel the deaths were at all related in cause. Thanks for the suggestion tho.