I have a bnp & bulldog plec in my 55. The past few days my bulldog has been attacking my female bristle, he's been jumping on her back & face causing damage to her eye & scratches. The only other tank I have is 16 gallons I,ve had him for over a year he's 2inches & the bristle is 5! Any ideas what I can do, don't like seeing her getting attacked had her since she was a baby. Any help please