Hi eliza, welcome to the forum.
My advice where to buy is the following:
Have a look around in several petshops in your area. Have a close look at all tanks in there. Are they spotless clean, are the fish happy wigglers, does it smell nice in there? No dead or listless fish in the tanks? Have a look at the plants too, do they look ok or rotten. How is the "hardware" displayed? Nice and all in order? How is the staff: knowledgeable, clean?
Maybe you visit the same stores at different times too, can you see staff members caring for their stock and cleaning tanks?
All this helps to decide where you get your fish from.
Do you already have your tank set up and cycled? How big is it and how many goldies do you intend to keep?
Just for general info: 10 gal minimum for 1 fish. What kind of goldfish do you fancy
Wishing you fun chosing your fishies
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