Well now Peace. At last a subject that makes sense. Good for you.
Now you might like to check this: Oh Goldie Pleeeeze
As you can see by this link extensive studies are being carried out as I type but as yet no conlusions have been reached.
My opinion (and it is not qualified) is that if it eats then it Farts and Burps.
I am sure than someone on the Mudcat with an in depth knowledge of Butt Thunder behaviour in Goldfish will no doubt contribute their thoughts and findings on this fascinating issue.
I will trace this thread to make sure I do not miss anything..
Jude..:>)