Clown fish twitching to mate or pair?

One fish swims to the right top corner of my tank and swims downwards and twitches. This occurs when the tank light is on or off, and also during the night when there is no light on (doesnt see its reflection). The other fish occasionally nips and rarely twitches, about 1/4 inch bigger and both were introduced the same time last week. Aside from that, they seem to get along well and swim around together. I understand that the twitching could be a form of what could possibly be the male bc he is smaller showing the female that he is being submissive and is not dominant. However, how do I know its a form of sumbission as opposed to the twitching seen in mating as well? Cant distinguish the two, and need help!

Thanks.

 

Hi

The female is usually the larger of the two.

Both clownfish will twitch, and your right is seems to be a sign of submission when the male does it. Male clownfish do it much more frequently than females. Clownfish breed around 2 - 2.5 years old. The difference between the male and female will become more obvious as they mature.

 

I had a pair of Ocellaris clowns a long time ago. The mating started with the twitching, followed by a horrible period of the female beating on the male. I don't remember exactly how long the aggressive period was, but it was bad. Just when I decided to split them up, the beating stopped and the became a happily married couple. Watching them lay and tend to batches of eggs is one of coolest things I have experienced in this hobby.
A pair of clowns will definitely be my first addition to my 125g when it's ready.