Hello, I recently bought a Rainbow Shark along with 3 Black Swords and 1 Comet Goldfish (biggest fish in my tank). I also had 4 Goldfish in my tank previously.
My Rainbow Shark has been fin-nipping every single fish in the tank, and I don't know what to do. Will it calm down after a while? This is the first day that it has been in the tank. It does go to some of it's hiding places, but when I feed my fish, it doesn't get the opportunity to eat much.
Also, my Rainbow Shark is the smallest fish in my tank, so it doesn't really have the ability to "hunt down" any other fish as they are all bigger than it.
Any ideas as to what I can do? I am considering giving it back to the pet shop.