Hi I have a bulldog plec and bristle nose in my 50 gallon, my bulldog who is 2 inches is bullying my 5 inch female bristle. He jumps on her back and rips her fin, won't let her eat, even tried feeding them at different ends of the tank which makes no difference. The only other tank i have is my 16gallon, any advice would be appreciated as i have had my bristle since she was tiny and don't like her getting hurt. Thanks