FE works but you need to try and remove as many as you can by siphoning first-be sure to do this!!!-then run the FE and have water ready to change-the fworms will excrete as they die and possibly toxify your water,hence the water change-did it on my 450g and worked great-skimmer will go nuts also-Joe
Flatworm Exit...just follow the directions.In my case I used it ,and cleared them out ,watch it for a week or so if you notice even one returning treat again and you should be free....