Took me 10 minutes of investagation. Im an 100%sure on this.They are getting ready to mate. The first sign is the MALE jercking one way and another for about 1 day, then the FEMALE kicks in and does the same thing to show that she is ready. There is no reason to be worried. This proccess could take from 1 day, to 5 months depending on the fish, and percs tend to be the fasted at becoming a mated pair. Very exiting to watch i might say. Again, i am 100% sure on this. If it was your water, the fish would be breathing hard and swimming side-ways. I have seen on discovery in time laps motion, the start of the clowns becoming a mated pair, and the first sing, is dancing, the second sign is "kissing" and the third sign is tackling eachother. I hope this helped!