I tried the wrasse route, but with no luck. I bought a six line wrasse to go to war with these darn flatworms, but I think they scared him. So now I need to bring in the big blue velvet machine. I am maxed out on the fish in my tank. I have a 40 gallon tank with 3 tangs, 2 clowns, 1 wrasse, 2 gobys and 1 puffer.