I'm still battling them on my two juvenile Muskie. Worst ectoparasite ever! I have added UV filtration to the system, so we'll see how that slows them (well at least the free-swimming ones).
Let me know how you do. These things are nasty to get rid of! I had to treat for weeks with a full dosage of diflubenzuron. It was the only thing that worked. I tried removing adults and everything. Eventually I just let the adults go and just kept dosing and dosing. The diflubenzuron breaks down the shell of the egg so they can't hatch. I had them everywhere at one point. Each fish had about a dozen small threads on them. It was very frustrating. Knock on wood that they are all gone. Last time I thought they were they showed up again, but that was only a few days. I haven't seen any in a few weeks. I treated one more time after the last two dropped off just to make sure that there weren't any that would survive. Somehow my crayfish lasted through all of the treatments. It was worse for me because I have a catfish and a lot of the treatments (like Clout) you can't use if you have scaleless fish.
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