goldfish with 10g tank?

Why not get a suitable tank from the get go?

If you cycle the tank first http://fins.actwin.com/mirror/begin-cycling.html a juvenile goldfish should be able to survive in a small tank, but it won't thrive and the longer it's in there the greater the chance of it stunting and having its life expectancy reduced. You will have problems maintaining water quality with a small tank which makes having to treat totally preventable illnesses more likely.

A common goldfish will get about 12inches long and live 20+years given the correct home and care.

it might survive but it will not be happy or healthy. it will be sad, unhealthy, and most likely will die. save the poor goldfish and wait until you can get the right size tank.

You should be fine with one goldfish but you must have a filter and heater. I have a 14 gallon with 2 goldfish and 4 tetras and they seem to be doing fine. :) If you have any other fish like tetras in the same tank with your goldfish feed them tropical fish flakes not goldfish food. I hope you get your goldfish. :D

yes for awile they can but if its a black moor or another kind like that they need 20-25 gallons to live.

Yes they can survive in a 10 gallon tank when they are small and has a good filtration. (They are quite messy) It might affect their growth rate too if they're in a small tank.

if you keep the water clean (filters) - it can live in a 10 gallon tank

Goldfish will continue growing regardless of the size of their tank.

We had one live for over 10 years in a 10 gallon tank and we kept the water clean by using a filter.

yeah it can but you will have to get a bigger one in a matter of months so its kinda a waste of money so i would suggest just buying a 20 gallon

but yeah they can live in a 10 gallon tank, but thats like saying a betta can live in a cup, they wont be as happy as they could be.