Aloha Don - Thanks for sharing your thoughts on my situation. You ask how long a parasite could live if all fish and water were removed. Well, I did remove all fish, and all water has been replaced........but keeping the system "DRY" or waterless would kill all the worms I have in there. I was hoping to have a solution which didn't involve that possibility.

I'm still halfway debating on running the medication through the system even though there won't be fish to medicate. My reasoning is that if it can cure fish from parasites, then perhaps it can cure water (or anything in the grow beds) from the same parasites. Again though, for all I know, my system could be parasite-free and I'm just drawing at straws with this one.

One thing I can't deny: my grow beds were FILTHY after TWO YEARS of never cleaning them. After I rinsed off the media and mixed it back into the grow beds, they unleashed a CRAPLOAD of floating particles into the new water I added. The water went from crystal clear to absolutely horrid. All kinds of floating junk (probably bits and pieces of roots, debris, old fish poo, etc) were dislodged and it makes me a little sick to know that all of that was residing in my system.