I've had a dog face puffer for 2 years now and I'm considering moving him from his current 55 gallon. He hasn't out grown of it yet but I am trying to start a reef tank and he would not be suitable. I'd move him into an 100 gallon with and eel and two groupers that are smaller than him. I'm not concerned about the eel because the puffer is housed with a snowflake eel right now and shows no aggression towards it. I fear he may try and kill the groupers because every other fish I put in the tank with him died. I first thought it was an undulated trigger that I had because he would go after the puffer and bite his tail. But the trigger died and now I'm wondering if it was the puffer the whole time. The trigger was completely healthy but the next day he was dead. I've never seen the puffer go after his tank mates except when I tried putting an angler in and he thought it was food.