What's wrong with my puffer?

[mikester311]

I have a 3" stripped puffer that gets freakes out every once in a while and rams it's face into the glass and zooms around the tank bumping into things. It's wierd because it's usually when the lights are off and all the other fish are sleaping. I also came out about 4 in the morning the other day and saw it puffed up for no reason?? It seems to be a happy fish that is always hungry and eats better and than any other fish in the tank. It's not being harrased by any of the other fish eather? Any ideas why it's freaking out? Has anyone else had this problem?
Thanks,
Mike

 

[mikester311]

The tank is a 72 bowfront. He has plenty of room right now I think? You may be right about his reflection though? I never thought of that but it may be a possibility. : )