i have had him about one month. he has only done it about 5 times... it looks like he is going to chase his tail and than he will flip to his side. and than sometimes flip to the other side. when he does it he does it slowly. iv also noticed today hes been more aggresive than he usaly is. he usaly doesnt mess with the damsel to much but he chased him around a good bit tonight...i think the fish looks helpless when hes doing all this...he two friends think hes ok....but it is bothering me