Goldfish parasite Argulus - I think??

Question

Hi, I've have had two fantail goldfish for a few weeks now and they've been really well. I went away for a few days and left an automatic fish feeder to feed the goldfish whilst I was away. When I came back one of the fish looked fine but the other had 3 quite big parasites on his body. Looking at images on the web it looks like the Argulus parasite. I did a partial water change, got the fish out of the tank and got the parasites of the fish with tweasers, removed all ornaments ,plants and carbon filters and added API Aquarium salt and Methylene Blue as instructed by my local store. Today his back tail has practically disappeared apart from a few hair like stems, it looks horrible and he's struggling to swim, he just floats at the top in a corner away from the current caused by the filter - he's not eating much either, he had one small flake in 2 days. How long should I give him to see if his tail re-grows or should I put him down. I down want him to suffer, but he's a plucky chap and would hate to kill him if there's any chance he could survive? Any help would be really appreciated. Thanks

Answer 1

The fin issue sounds more like a result of overfeeding from the automatic feeder than the Argulus.  The best way to deal with that would be more frequent water changes.  Adding salt and methylene blue will actually be far more effective in preventing the tail from getting infected than treating the parasite-- manual removal with tweezers would be a better idea, and then dabbing methylene blue onto the wound, and keeping the water salted and treated with methylene blue to until the wound heals to prevent future infection.  His chances of survival are very good at this point, and quick treatment will greatly increase his odds.