I would take some Seachem Stress Guard, a turkey baster and skirt some directly on the wound, then dose the whole tank. It wont hurt anything. Some aquarium salt would be a good idea too.
no way! I love my piranha as much as I love my shark ^^
I'd love the serrasalmus family ^^
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The only reason the piranha got a chomp of my other fish is I was cycling / setting up his tank, but then he jumped out of the holding basket, luckily he didnt snack on my smaller datnoid, else I'd choke him!!!