Question
I have a small pond in my back yard (90 gallon).  I started out with 12 small goldfish and after a couple of weeks, 5 died.  The remaining 7 have grown to 3-4 inches.  They are doing great.  I had one black one but it turned orange like the others.  It's going to get cold here in Massachusetts by the coast and I don't want them to die.  I was going to bring them inside but am not sure what size tank to use.  Someone told me that a 10 gallon tank would be too small.  What do you recommend I do for the winter?
Thanks.

Answer
I'm sorry so many died but glad the rest are doing well.  Goldfish often change colors, especially when young.  Because you're in such a cold area, the pond will probably freeze too much to keep the goldfish outside.  I suggest at least a 20 gallon tank.  You can also use Rubbermaid or Sterilite storage tubs/containers which will give you a larger "tank" (really an indoor pond) for less money than a more expensive glass aquarium.  If you use an open indoor pond, then you may want to net it to keep the fish from jumping out.  I keep my 20 gallon indoor tub pond in the basement.  When I have fish in there, they don't need to eat much since it's cool down there.  Eating less means less waste and less cleaning as well.  It's up to you how warm and active you want to keep the fish.  If you have a garage that goes almost down to freezing (as long as it doesn't freeze), you can keep the goldfish indoors but hibernated (no feeding).  You can also keep them at room temperature and feeding and growing.  I've done both but you can enjoy them more in a glass aquarium and active.  Good luck!