Of course they are hun!
Utter rubbish. Most fish that are well acclimatised to the lower temperatures we are having will be in a state of semi hibernation. Any fish swimming close to the surface now will be taken out by herons but on the bright side at least that is nature taking it's course.
'Such high emotions for... er... goldfish.'
Er yes! A life is a life and when you take an animal in to your care you should, as I have said before be prepared to care for that animal to the best of your ability.
You may have even committed an offence...
https://www.gov.uk/non-native-fish-and-shellfish
God help your other animal when they become ill, old or injured, what will you do then, toss it into the trash? Grab a new one?
Lucky we don't do that to people when they 'break' isn't it!!!!