I had fw really bad a few months ago and didnt want to go the fwe rought so I bought a wrasse from House of fish. I'm not really sure what kind of wrasse it is but with in a cpl of weeks they were all gone and I still have a beautiful wrasse. If you decide yo go the same rought as me just drop Jim a line and let him know whats going on and he will fix you up. Good luck
You can also try manual removal before using Flat Worm Exit. I took a small acrylic tube and attached airline tubing to it. Then ran the tubing into my filter sock. Start a syphon and you've got a vaccum cleaner to suck out the worms one at a time. Do this for a few nights in a row and then FWE to get rid of any you cant see. Carbon and H20 change afterwards.
I have a yellow coris wrasse, if you want to buy one in manhattan. I bought it for the same reason(FW removal) and they are almost gone(I also have a xmas wrasse, so he can finish them off)
PM me if interested...
I have used FWE before, but it is better to get a wrasse(the less chemicals in a tank the better)