Fish zole is actually an antibiotic. It's Flagyl in human terms. It treats some of the toughest bacterial issues. Metronidazole. It just also happens to kick butt on parasites as well. After trying everything I could find over the counter, I looked at the sticky thread in this forum that discusses meds. It recomended Metronidazole which worked great. I'm just thinking that it could be a very good choice for covering multiple bases.