what are they?????

[Doug]

Stupid 6 line wrasse. Dont forget how aggressive they become as they age. Many other more docile fish , if thats the route one wishes.

Plus, using fish to get rid of flatworms is a 50/50 proposition. Some do eat them some decide to heck with it. Mandarins eat them but I dont believe enough to keep up with reproduction. I think many have had luck with a yellow canary {banana} wrasse and they seem to less aggressive than 6 lines when mature. Same with leopards.

No matter which method you choose, as Brad said, siphon, siphon, siphon. Keep changing your filter media, sock or whatever it is you use and keep fresh carbon in to remove any toxin from dead flatworms.