Acan Acting Like Puffer Fish

[Marco S]

I have 4 Acans in my 20 gallon Coral QT Tank. All of them are growing well and looking great. The newest one I added is much bigger than the others with about 25 heads. It has many different colors from purple to red, yellow and white with a pinkish center. It was pretty flat when I got it and after a few days it puffed up like three times it's size and stayed that way all day. At night it went back down and it has been doing that ever since. Sometimes it puffs up so big and fat I think it's going to explode! It gets huge and the polyps actually sway with the flow like they get more jelly like the bigger they get. I read that some coral do this to expel sand and some when they are expelling Zooxanthellae, but it never expels anything that I can see and it's colors are more vibrant than when I got it so it isn't bleaching and I don't think it is stressed...

Is this normal or is this a bad sign? And if it is normal, should my other Acans be doing this also? Or is it only specific Acans?

Note: I know that Acans have been reclassified Micromussa Lordhowensis, but I call them Acans because that is what they are to me.

 

[doodledreads]

Its pretty normal behavior. I noticed some of my acans do it more often than others. I believe they do it usually to flush out the sea water and pump fresh sea water in. A lot of lps and nems do it too. As long as it is happy and goes back to being puffy, I wouldn't look too much into it.