clown fish aggression over anenome

[clarence]

I recently purchased two fairly small percula clown fish. They were doing great and being quite chummy. Today I purchased an anemone for them which they both took to right away. They have not stopped fighting to push each other out since. They are concentrated on this completely ignoring food. I tried placing a mirror on the glass in front of them but this only created a brief distraction. I guess they will stop when the lights go out. Looking on line this seems to be not unusual . Any encouragement or suggestions appreciated.