Clownfish mouth movement

[goldenroot]

Ever since I got them about three months ago my clownfish have been opening and closing their mouths, but have seemed otherwise fine in that they seem to be eating normally and don't seem to be acting sick, so I have tried not to worry too much. In the past couple of days I have noticed that when they eat some food their gills will start to move(pump?) despite normally looking fine, although this may have been a long term thing that I just noticed. I feel like I should also note that the royal gramma in the tank is not doing any of this despite having been there for months already. Is this a problem, and if so what should I do?
Video of the clowns in question

 

[kfisc]

The clowns I had (a pair of maroons) were very animated when they ate, spitting food out and rechewing it again, etc. From what you've described, I wouldn't worry about them.

 

[leebca]

Ever since I got them about three months ago my clownfish have been opening and closing their mouths, but have seemed otherwise fine in that they seem to be eating normally and don't seem to be acting sick, so I have tried not to worry too much. In the past couple of days I have noticed that when they eat some food their gills will start to move(pump?) despite normally looking fine, although this may have been a long term thing that I just noticed. I feel like I should also note that the royal gramma in the tank is not doing any of this despite having been there for months already. Is this a problem, and if so what should I do?
Video of the clowns in question

Thank you for the video. It helps.

I'd say the fish look to be okay. Try to vary their diet. Download then read, the Fish Nutrition document.

Marine fish 'swallow' water to get oxygen from it. The water passes through the mouth and over the gills where gas exchange takes place. The fish I see are normal.

There are conditions where the fish open their mouth's very wide but I don't see that here.

 

[HumbleFish]

I can't see the video. Does it look like the fish are "yawning"?