Yawning goldfish?

Question
Hi James,

I am an experienced tropical fishkeeper but relatively new to the goldfish hobby.  I have a juvenile Ryukin in a 10-gallon tank.  It's a little on the warm side (78), but I do have a bubble curtain and am trying to lower the temperature gradually.  I use live plants and do 20% water changes twice a week.  The tank is fully cycled.  

I have observed a behavior in my fish that I've never seen in tropicals before.  He opens his mouth really wide, like he's yawning or taking a big gulp of water.  He never gasps at the surface, so I don't think it's a problem with lack of air.  Any suggestions?

Thanks!

Answer
Hi Lauren,

I get this question alot.  It is either very good or a little bit bad.  Most ryukins and other fantail goldfish will 'yawn' just to stretch their gills.  This means that they are very comfortable :).  But sometimes, they will do this because they are lacking oxygen (which you most likely know).  If you are worried about the oxygen, why not just get a cheap pump and airstone.


I hope I helped,
James