Bringing Pond Fish Inside for Winter

Question
QUESTION: Hi there,
I have 3 goldfish that survived the summer in a 50 gallon pond. I live in Minnesota and the pond will completely freeze so I would like to bring the goldfish inside. I am wondering how large of an aquarium will be necessary to contain the fish for the winter. I have read 10 gallons for each fish, so 30 gallons. I'm on a budget and am wondering if this large of a tank is really necessary?

Thanks

ANSWER: How many inches are the goldfish?

---------- FOLLOW-UP ----------

QUESTION: The fish are probably 3 inches long each.

Answer
You can get by with a 20 gallon tank.  I know the rule of thumb is one goldfish per ten gallons of water but this is not going to be their permanent home and they are not too long for a 20 gallon tank.  A 55 gallon would be the best option.  All that you would need for them is the tank, light, heater and filter... You do not necessarily need a stand. If you have a garage they will do just fine in a tank on the floor of the garage.  If you need additional information or have other questions please let me know... dave