Regarding the drug mentioned.
The drug name is Metronidazole, and it is commonly sold under the brand name Flagyl - it is a human drug and requires a prescription...but...
Aquarium places can sell this over the counter labeled for aquarium use. It is exactly the same med you would get at the drug store with a prescripption from your doctor. I believe the commone "aquarium" brand is called "Fish Zole." You may want to call the aquarium shops in Portland and see if anyone has it.