Hello I am looking at buying a garter. Now I don't mean to be any hassle.

But if you guys could answer some questions I would be more than grateful...

What size aquarium around and will it need to be heated?
I know goldfish and frogs, but what is the best food and how often?
What sort of stuff should I be putting in the aquarium(stones,Water etc.)
Any other important information would be greatly received!!

Thanks in advance, AB