I have a well run in tank about 12 months i got a fighter about 3months ago and all was fine. In the last week or so he has become a real pain nipping Black Mollys and the odd guppy. Just wondered if there is anything i can do to keep him busy. I have been told put a ping pon ball into the tank and he will play with it. Sound daft but he does mess around with it buut still nips.