So I recently set up a new 10g tank with an iridescent shark, a zebra loach, a rainbow shark, and a boesemani rainbowfish. Unfortunately, the shark has been nipping the boesemani's fins any chance he gets, ignoring the other fish. Is there a way to stop this? Should I get more rainbowfish, or take the shark back? I would like your guys' input as a side question, why is my zebra loach hiding so much? Does he require a shoal of more loaches to be social? I'd be grateful to get any of these answered!