Injured fantail :(

Ahh. Thanks for all your replies..

This morning she is swimming all around the tank, and looks very healthy; her sores have healed quite well, and she is eating.
Honestly, I have no idea how she has recovered so quickly.
Anyway, I know I can't afford a bigger tank for her, so if she continues to stay healthy, do you think Petsmart, or a LFS would take her?
probably, but I might put the effort into finding a good home for her. you don't know where shes gonna go at petsmart or an LFS unless the LFS or petsmart is a good one that only sells fish to people with proper tanks lined up.
 
So I would need at least a 20 gallon tank, right?
I wouldn't put a goldfish in a 20G, simply because of how much waste they make combined with the fact they can get to 8" long. i'd get a 30G for it.
 
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