i have 5 aro in a5x3x3 tank,three slighty bigger ,last month 2 of the bigger ones started to swim together ,sometimes in circles,sometimes together at the bottom side by side,the last week one of them would wiggle and then swim away,now one chase the other wanting to bite,from my last posting they both hve spilt lower and tail fins, so i took 4 out leaving the most aggrasive one remaining in the tank.one would think that one is male the other female,but i could not tell them apart...hence the Question,