Why is he doing this???

We only acknowledge that boys do the "#2". Certainly if the anemone was a she, she would not be doing such a thing.
 
Its a Condylactus Anemone... They do this about once a week (the times you notice) and most of the time they do this at night, when the lights are out. Its not expelling waist, its just expelling all the water it had to gather up new one, after they do this cycle they look much nicer in the morning... its what you would consider "a nap" I have two in my tank and the first time I saw one doing that I thought it was dying (I had only had it for two days) I took it out, put it in my qt and took it to my lfs the next morning they explained to me how it works and have had them both for about a year now. If you put a clown they will love each other.
 
By waste Don, I'm speaking of the toxins in the water it has inflated with. It is very common. I'd not recommend getting a clown for it in the hopes of the clown accepting it as a host. There are far better anemone hosts for a clown.
 
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