Carmen not eating

Question
Dear Nick
I wrote to you recently re Clementine.  Sadly Clementine passed away.  Having not lost a fish in over a year, it was very distressing.  Now I have another problem, Carmen (named after Carmen Miranda) who was part of the 1st lot of fish I ever purchased about 2 years ago is an oranda and I noticed she hasn't eaten for some days.  She takes in food that is floating by and spits it out again.  She is swimming but is listless mostly preferring to hang near the bottom.  She looks perfect.  Her eyes don't seem as vivid as the other goldfish, but I don't know if she has always had these eyes or if they have changed.  She is 8"/20cm.  The water is good.  I am now changing 50% of the water as suggested on a weekly basis.  

Thanks again for your help.  Don't know what is happening with the fish babies.
Kind regards
Mattie

Answer
When she spits out her food she is saying she does not like it. Try different foods with her. Frozen tubifex or slices of orange are rarely turned down by fish.

It is preferred to do 25% weekly, but you can do 50% of course, as long as the water you are changin is the EXACT temperature of the water in the tank. Be very careful with that.

-Nick