I have a 2.5" oscellaris in my 55 gallon that has been in there for a couple years. I assume it has changed to female since it has been alone. If I add a small oscellaris to the tank will the larger kill the small or will they try to become a breeding pair? My tank contains about 45 pounds of rock and a clay pot that I cut in half. I figured the addition of the clay pot would allow them to use this as their home.