Parasites

[Yetti]

Yesterday I have noticed that one of my two young angels has some stringy thing on its fin, so I carefully observed it, and it seems like a parasite of some kind. Today when I looked at the thing it lost its tail, probably the other angel bit it off, and I also noticed that there are more of them in the filter tubing ( transparent tube).
The thing is about 2 to 3 mm long, tomorrow I will be going to a lfs, and could I get some advice on what medication to get (I live in the US).
Thanks

 

[WILDER]

Does the parasite have a forked tail.

 

[WILDER]

Did it look like this pic, if so anchor worm.