What do you feed them as a hatchling and when their an adult? Could you feed them the minnows that you can buy as fishing bait?

Most people feed them floating pellets/sticks, aka - "Turtle Food". As a hatchling I would give them worms, feeder fish, turtle food and maybe small crayfish. Same as adults... except in larger quantities. Fishing minnows are fine...

I live in Minnesota so we have somebad winters. Is there any softshells that I could keep outside year round?

There are softshell turtles in Minnesota...

How deep should the water be in the pond? How big should the pond be?

I would say atleast 3 feet deep.
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Mike
KingPin Reptiles Inc.
Diadophisdude@yahoo.com
www.freewebs.com/mikesnake