do flatworms ever go away

[Doug]

Way back when, I found my mandarin, and wrasses, who all ate flatworms, could not keep up. I eventually did the Exit, several times as mentioned above. Losses are usually from the flatworm toxin as they die and not the exit itself. As others said if you do go this route, lots of carbon and good mechanical filtration, with media changed a lot.
I also ran my skimmer full bore to help, even though it likely removed some exit.